Archive of Our Own

Art by maggishiani.

Deku used to be worthless and weak, Katsuki thinks, looking at him only because the class is boring and the hag at the front is just droning on and on and on. But now, Katsuki sneers, he’s worthless, weak and also an absolute weirdo, look at him talking to his hair again.

Katsuki will never admit it, because doing so would be admitting weakness but sometimes, when he grabs Deku from behind or when he bumps into him after a corner, it hurts looking at him. Katsuki would see green, green, green, his eyes would latch onto a green that’s unlike the color of Deku’s hair and his mind would fill with static. For just a second, no, less than that, a fraction, really, Katsuki would imagine the green to smell like unexplored ocean ruins; he’d imagine the green to sound like a storm creeping closer, violent winds battering against his chest, robbing him of breath.

A tiny fraction of a second. A negligible amount of time, insignificant in the context of his lifetime.

And yet.

His heart does not stop its wild, frenzied beating for long minutes afterwards.

Katsuki would never admit it, but on those occasions when he catches Deku unaware, he feels the kind of fear that comes from the primordial unknown, from elemental uncertainty. It spikes high from beneath his ribcage and travels lightning fast upwards, shooting through his heart and then down to his hands.

Fear is encoded in sweat; the more intense it is, the higher amount of volatile molecules are emitted in sweat. And nitroglycerin is an extremely volatile chemical.

Katsuki is too young to realize why Deku’s clothes are easier to singe and burn than anything else; Deku is Deku, of course the things he wears are as useless as him. He turns his attention back to the front just in time to hear the hag ask him a laughingly easy question. Of course he answers correctly. No challenge at all. He goes back to stare at Deku, who is now smiling at his shoulder. Fucking weirdo.

Deku would be slightly less useless if he admitted the quirk he claims to have is a fake to try and blend in. Katsuki snorts. A door. Was he for real? As if no one else could imagine a door. Absolutely fucking useless.

(Some nights he dreams of the deep dark of the ocean and of green that hurts to look at.)

Izuku thinks it's a normal thing, that everyone's born with a looming door at the back of his mind. Big and imponent, always open to some kind of hazy and swirling darkness, just being there. And that's just the thing, isn't it? We see and experience the world through the lenses of our own involvement; Izuku's door is as much a part of him as his eyes, or his belly button, or his toes. Inko's got eyes and a belly button and toes just like him, so really, why would Izuku think his door was something unique?

Three weeks past Izuku's fourth birthday something changes. The lazy eddy of the darkness beyond his door suddenly agitates, it rises and surges at the edge of the threshold like an angry wave against the shore. It crashes down and the door shakes once, twice; it groans as it slowly turns on its hinges until it closes completely. The steel-like material of its front shifts and twists up, not unlike tentacles, to form a shiny, comically oversized padlock.

It’s actually not until three months after Izuku’s fourth birthday that he sees a padlock very much like the one on his door and he asks his mother why his does not have a keyhole.

Inko, taken by surprise while she’s puttering about the kitchen, asks back rather absentmindedly, “Mmm? What was that, honey?”

“My door,” Izuku points to his skull, little chubby finger getting lost in the wild tangle of curls, “doesn’t have a hole.” He points now to the TV where the cartoon he’s watching was displaying a padlock three minutes ago but not anymore. “Why?”

Blinking, Inko tries to puzzle what exactly is Izuku asking but ultimately fails. “Doors shouldn’t have holes, darling, that would mean they’re broken.”

Izuku’s nose scrunches up in frustration. “No. Not the door, the door.” He brings his hands up and down, like they’re fangs biting at air, “with the key!”

Thankfully, the cartoon chooses that time to display the padlock again and Izuku runs to slap the screen pointedly, “See! It has a hole for a key! Mine doesn’t! Why mine doesn’t?”

It takes the whole afternoon for Inko to suss out what exactly Izuku is talking about but at the end she decides it could very well be Izuku’s quirk. She’s ecstatic and a date with a quirk counselor is set for next week.

It takes days and days of sessions and questions and testing but they do finally come to a conclusion. Izuku’s door is a quirk.

They’re not exactly sure what kind; there’s one like it in which the door serves like a portal that the user can teleport with, there’s another that can use it like infinite storage, yet another that can use it to call forth abyssal shadow-like creatures. They decide to call his quirk gatekeeper.

Izuku can touch the door with his mind senses: he can describe the smooth, cold metallic surface; he can, to both the doctor’s and Inko’s panicked dismay, affirm that it tastes like the door handle of his room; he can hear the darkness beyond like a muted breeze through the park. What he has trouble with is describing size (“It’s big,” he says, opening his arms so wide his hands touch behind his back, “big and to the roof.”) and color. In fact, as it becomes clear when they show him an extensive color wheel, the door’s color doesn’t seem to exist. They ask Izuku if he’s seen that color before and Izuku shakes his head. He’s only ever seen it on his door. Then he pauses and tilts his head, humming. No, he finally says, he sometimes sees it beyond the door; within the swirls of the darkness, sometimes the color will shine through, like when light hits soap bubbles.

They keep asking questions and Izuku is ecstatic. He has a quirk! A quirk so special it has a new color even! Really, the only thing he doesn’t like about it is that he can’t draw it because not even all his crayons put together can recreate the color of his door. The counseling sessions stop when nothing else can be gleaned other than Izuku’s quirk seems to be passive, probably awaiting some kind to trigger to fully show.  

Just because he can, because it’s his quirk (his quirk!), Izuku spends days opening and closing his door, again and again and again, until the hinges no longer squeak and he can move it swiftly and smoothly, either too fast to see or too slow to show.

The door is kept open because having it closed feels weird; he likes the shifting darkness. Likes the rare glow of colors he has never seen outside, likes the peaceful cold that seems to emanate from it, how it feels a bit like coming into the cool inside of his home after a day of playing under the sun.

It hurts when Kacchan laughs the first time Izuku tells him about his quirk.

It hurts a lot when everyone else says he’s lying.

It hurts the most the first time Kacchan calls him quirkless and it never stops hurting when everyone else says he should stop making up a lame quirk and accept what he is.

For years and years Izuku does not talk about his quirk. He experiments, though. Keeps several notebooks of observations and failed triggers, has a tracker of when the unearthly colors show up to see if there’s a pattern (conclusion: there’s not) and he chats about it to his mother, trying his hardest to describe the indescribable beauty of his door and the darkness beyond.

So yes, for years and years he doesn’t really talk about his quirk, for fear of inviting more ridicule. And then.

Then, he gets a new reason not to talk about it.

He's one week shy of turning twelve when someone, something, comes slithering out of it.

With a startled gasp Izuku realizes he’s made one terrible, obvious mistake. Wasn’t this even touched on that vintage superhero movie? He’s been calling the door his, but who’s there on the other side to call it theirs?

The kitchen chair he’s sitting in makes a piercing screech when Izuku violently stands up, then crashes loudly to the ground when Izuku tries to quickly step back and gets tangled in it. Izuku’s face is as white as the sclera of his impossibly wide eyes as he tries his best to scoot away from the myriad of writhing green tentacles that have materialized around him.

And there are a lot of tentacles. Entirely too many tentacles. There are, in fact, more tentacles than ought to be able to fit inside their little kitchen. Izuku’s dazed and trembling; it’s not just the tentacles that have gone wrong with his world. The kitchen doesn’t look quite like it should, the light is wrong in ways that make Izuku’s breath hitch and the cabinets have twisted somehow, occupying space in a way that cannot be described by human logic and it’s making Izuku’s head throb with the impossibility of it all.

Colors that reach beyond the bounds of reality, those which he’s only ever seen on his door and its darkness, bleed into the floor like an oil spill. They move with purpose, like pulsating slime mold, with a sort of sentient calculation as if they were looking for something (escape? Izuku’s mind hysterically suggests, food?) and slowly engulfing the whole kitchen floor. His heart is beating like crazy and he can barely breathe, his lungs working too erratically to drag in air, his head is drumming up a pounding staccato of pain that is becoming sharper and sharper the longer he looks at the writhing mass of appendages and what seems… like… eyes…

He screams just as his mother rushes into the kitchen. Izuku doesn’t know exactly what happens, but all he hears is his mother’s agonized cry and when he opens his eyes the kitchen is back to normal and his mom…

His mom is unconscious on the floor.

He wants to rush to her but his head is filled with static and his blood is thundering away behind his ears. He hears a voice deep as a cavernous mountain that makes the hairs of his arms stand up. Danger lurks like a promise in that voice, carrying a hint of unfathomable madness. Izuku thinks, in one second of frantic clarity, that the voice reminds him of the Bolton Strid, the little and unassuming stream that looks like all the other little, unassuming streams around the world but has drowned every single person to ever step in it.

 And rising above it all, carried on that voice, a whisper of a name.

Cthulhu.

Anxiety is, to put it mildly, a bitch. It makes Izuku have a compulsive urge to be polite to everyone, to aim to please, and fighting against this impulse is akin to swimming upstream in a river with strong, violent currents. This is what Izuku has to fight in order to close his door on Cthulhu’s face and firmly lock it shut.

He expects to miss the soothing darkness, the cold and the colors, and he does, but he had mentally prepared for that. What takes him by surprise is the mental exhaustion creeping like fog across his brain and Izuku realizes that, for all the experimentation he’s done on it, he never once kept his door locked for more than a few days. It felt so natural for it to be always open, just like it had been since Izuku was born.

Three weeks later and Izuku’s focus is sand between his fingers, slipping away from him. He wonders if this is quirk exhaustion settling in.

Izuku is stubborn, though. He’s self-harmingly stubborn. He endures the exhaustion, the pain behind his eyes, the loss of focus and the way his body is screaming at him to take a break. He’s only a child, however, and he soon reaches his limits. It's but a moment after he's just closed the door to his bedroom that the world tilts sideways and his vision goes dark. He’s already lost his consciousness when his head hits the floor with a muted thump.

When he comes to again, it’s to his mother’s worried face. “Izuku, what happened?”

He tells her about how he tried to keep the door locked for as long as he could and how he didn’t know it would affect him like this. He starts babbling about quirk exhaustion and time frames when Inko gently cups his face and asks: “Is the door locked right now?”

And to Izuku’s absolute horror, it is not.

He knows he didn’t unlock it, he knows, with absolute certainty that he lost consciousness with the lock firmly in place. Inko directs him towards his room, where he sees his bed now broken beyond repair, folded into itself like a paper ball. His pillows are placed on it like cherries atop ice cream, and it feels like a mockery, that the pillows are now the same impossible color of his beautiful darkness.

This is how they discover that the effects of Izuku’s quirk disappear with his consciousness.

Cthulhu comes and goes like a tsunami. He will leave for days and weeks and then come back and wreck Izuku’s day. Cthulhu seems to delight in making one of his tentacles appear out of Izuku’s hair when he’s talking to cashiers to make them go mad and indisposed, thus preventing Izuku from getting groceries. Or just living a life, actually.

And then one day, Cthulhu tires of visually inducing madness and alters reality.

Izuku stops, mouth gaping open at the absolute non-euclidian mess that has become of his room.

His bed is stretched to infinity and his closet has what looks like a black hole beside his All Might hoodie. His bookshelves are replicated atop each other, the shelves acting like steps. They form staircases that fold and coil over themselves and go into his walls only to come out from a ceiling shattered in dozens of mirror pieces. Some disappear into blurred out corners, one even ends inside his open notebook.

Izuku takes the staircase-repurposed bookshelf that goes inside the notebook and he can actually feel himself shrinking, can feel the strain of his bones, the spams of his muscles, the ever growing slight loosening of his clothes. He backtracks quickly when it starts to turn painful and he thinks, had he kept on going, he would have ended up a minuscule corpse inside his notebook.

It’s unbelievable. It's impossible. There shouldn't be a quirk capable of altering reality on this scale.

“This-this is so cool!” Izuku forgets about the torment that has been every Cthulhu visit day, and turns to look at him with a beaming smile and starstruck eyes, because his room looks like an Escher painting and Cthulhu did that. Cthulhu can actually do this. “What else can you do?”

And Cthulhu must enjoy an audience because his laughter ripples through the walls, leaving abyssal cracks behind, and shows Izuku what else he can, in fact, do.

Like this, Izuku's friendship with Cthulhu happens exactly the way Cthulhu came into his life - abruptly and chaotically.

Izuku completely and irrevocably loses his fear of Cthulhu like this: he's scouring the net in search of every morsel of information on Cthulhu's kin and asking him to verify whether they were true or not. Cthulhu can fly. Cthulhu has literal supernatural strength. Cthulhu can breathe underwater; Cthulhu, in fact, can comfortably live in the void of space and in the vacuum of black holes. Cthulhu is not even the strongest of his kind and he’s still almost indestructible. He has a millennia-ongoing feud with Nyarlathotep who Cthulhu apparently loves to hate.

Izuku hums as he clicks on a page with a clickbait-y title, hoping for some outrageous claim to see how Cthulhu would react to it. His eyes alight.

“Cthulhu-san, it says here you can create a city out of nowhere,” he swivels in his chair, legs swinging giddily and he grins at the Old God, “is that true?”

Cthulhu scoffs and places his hand on the floor and when he lifts it, dozens of little tiny buildings rise with it. A few keep growing taller and taller, until Izuku realizes they’re skyscrapers. Not a second later a delighted gasp escapes him when he recognizes the perfect miniature replica of Musutafu.

“Cthulhu-san, this is amazing!” Izuku scrambles down from his chair to kneel at the edge of the city. “Everything looks so perfect, there’s school and four blocks away there’s Fujiko-san stationery shop!” Izuku looks up, still beaming. “That’s where I buy my notebooks, she gives me a bundle discount if I buy more than four. She’s very nice and has a really cool quirk! She can blow shaped bubbles! And I asked her and they’re unpoppable, and technically they aret, she has to will them to burst so she always uses her bubbles as decorations, she once had a highly detailed, almost life-sized lion! I wonder if she could make bubbles big enough to contain people, if the bubbles can’t break they could work like containment and-”

Izuku’s excited spiel is interrupted by a ping on his phone. He crawls back to the desk, stretching one arm to blindly grope around the surface for it. He can’t find it so he sighs and stands up only to realize it’s not on his desk but on his bedside table.

It’s a message from his mom, asking him if he wanted some freshly made peach daifuku. She’s going to take some to Mitsuki but she's left several on the counter for him to take.

“Mom made daifuku!” Izuku says, lifting his gaze towards Cthulhu, who was busy poking the floor to create little human shapes all over the city. “You should try them, they’re the best, I’ll go bring some.”

Under a light cloth on the kitchen counter, Izuku finds several peach-shaped desserts. Inko likes going all out when she’s bringing them over to someone and they look both tasty and cute. Izuku takes two, stops, looks in the direction of his bedroom, then takes two more.

He can’t resist biting into one and he hums with happy satisfaction as he steps into his room. He pauses for a moment before gaping at the absolutely bizarre view inside. Still next to his miniature city, Cthulhu has discarded the little people in favor of Izuku’s hero figurines. The old god has Ryukyu in one clawed hand and he’s having her fight an Edgeshot perched on the tallest building.  

Izuku can also see Wash, the laundry hero, laying on top of Endeavor on another building. He’s still processing Cthulhu playing doll house when he sees a green tentacle stretch from Cthulhu’s face to wrap around one of his limited edition All Might. He doesn’t think, he just sprints forward to slap the tentacle away from his treasure.

“That’s a limited edition!” He yells as he scrambles to catch the dropped figurine one-handed before it falls to the floor.  He succeeds and sighs in relief, then rounds on Cthulhu. “You can’t play with this one, it’s super rare!”

Cthulhu starts laughing and sticks him to the ceiling. The old god does not stop playing with the figurines, but he doesn’t touch the ones Izuku tells him are too precious. Izuku gets unstuck after a couple minutes and he finds that he can’t feel afraid of him anymore.

He also finds that Cthulhu loves his mother's peach daifuku.

The first time Cthulhu hangs out with him at school is also the first time Kacchan hurts him for real. His explosion is stronger, hotter, and it burns through his uniform and through the first layers of skin. It hurts. It really, really hurts.

The pain gets compounded by the headache he’s getting because it turns out that, before, Cthulhu had never truly tried to break free from his locked door. Now the old god does try; his fury and murderous roars make his mind see stars, terrible blows shake the frame and his body trembles with the violence of Cthulhu’s attempt.

Izuku is glad he instinctively locked the door when he saw Kacchan’s hand land on his shoulder. He knows, with the same wisdom of that instinct, that were he to unlock it, Kacchan would be no more. So he picks himself up, steels himself against the pain on his body and the pain on his mind, and drags himself home.

The walk back is made significantly easier when Cthulhu realizes he’s hurting Izuku and stops his assault on the door. They’re more than halfway through the way home, though that means nothing to someone like Cthulhu who can probably traverse great distances in a heartbeat, but still, tentatively, Izuku unlocks the door.

“Will you-” he’s just barely started his question when Cthulhu’s voice drowns out his.

Cthulhu rages and rages, vows to pay Kacchan's pain back tenfold, promises to erase the teachers who let it happen, and when Izuku tells him that it’s normal, that hae’s used to it, Cthulhu pledges to excise from existence everyone who’s ever looked down on him. Izuku is not inferior. Izuku is brighter, better than any of those worms. Izuku is Cthulhu’s and therefore not allowed to suffer.

Izuku lets him rage; lets him roar out his protectiveness. He shouldn’t smile, shouldn’t do anything to encourage this kind of behavior, but never before has anyone cared for him like this. So unmistakably, fiercely.

“Thank you, Cthulhu-san.” His voice is wobbly and there’s not a space on his cheeks that is dry. He tries to dry his tears but it only makes his sleeve wet. Cthulhu’s anger simmers down to an indignant grumble and pointed comments. Cthulhu demands a promise and while Izuku is presently very grateful for Cthulhu’s violent showing of his care, he still cannot promise not to lock the door if something like this happens again.

The next day, Izuku wakes up to his room stretched beyond the limits of physical laws, his furniture fashioned into obstacles along a line that looks like a race track. He’s totally dumbfounded and Cthulhu takes advantage to pick him up by the collar of his pajama shirt and unceremoniously drop him along the track.

“Cthulhu-san, what…”

Train.

Inko arrives home only to find the living room rearranged into an impossible, chaotic mess. She quickly slaps a hand over her eyes, before the sight does more than the headache she feels pulsing against her temples, and yells in what used to be the direction of Izuku’s room.

“Izuku! How many times have I told you to tell me if Cthulhu-san is going to alter home?”

She hears a crash and a yelp, and feels pressing against her chest something like the harsh gritting of teeth if teeth were instead made of concrete walls that she knows it’s Cthulhu’s laughter when she hears it muffled through many, many layers.

Then a door slams and Izuku's hurried steps come to a stop next to her somewhere on her right.

“Sorry! I’m sorry, mom!” He’s so out of breath he’s panting after every word and Inko can easily picture him doubled over, hands on knees, trying to get his breath back to normal. “We wanted to test several training grounds for maximum efficiency and then of course we had to actually try them, we were supposed to finish before you came home but then we lost track of time and I’m so sorry! It won’t happen again! Are you okay?”

By the end of Izuku’s explanation and apology he’s out of breath again because her reckless, brilliant kid said it all without taking a pause for air. At the same time, from her left side, she feels the grocery bag being gently taken away from her and picks up the rustling of someone going over its contents.

She can’t help but snort. These kids. “I’m okay, honey, I just had a bit of a headache when I came inside. Be more careful in the future, please.”

Inko doesn’t have the words to explain the sensation that washes over and through her, she knows it’s the fabric of reality realigning to its normal state, has felt it enough times since the moment Izuku told her Cthulhu was going to do some kind of trippy training course for him. Because apparently Cthulhu was offended by him being too weak.

Izuku said it with a roll of the eyes, like it was something like an inside joke, but she knows it was because her baby, strong and determined, would never ask someone else to fight his battles. More than that, Inko knows that her sunshine child with the softest of smiles and even softer heart would never ask someone with inhuman morals to unleash his chaotic power on anyone else. She knows her kid and so she knows, without a doubt, that not even in self-defense would Izuku let Cthulhu out for his own sake.

And this terrifies her and makes her so proud of Izuku at the same time. She’s so scared of what a future in heroics would bring for him, when he’ll use his quirk to protect his enemies instead of himself. And oh, how it hurts, just the thought that her baby will one day have enemies.

“I’ll be more careful!” Izuku promises, and Inko opens her eyes to the sight of a normal home and her son’s bushy head as he hugs her.

Izuku’s hold is much stronger than it was months ago.

Inko doesn’t have the financial stability to get him actual trainers and it makes her so glad her baby can still get this, unlikely and otherworldly as the source is. Izuku is smart and resourceful and he took that opportunity seriously. She’s caught him carefully researching proper techniques for weightlifting, heard him thank Cthulhu for saving him from a bad fall, and most importantly, seen him light up bright and happy when he shows her the first time he successfully masters a parkour trick.

“I know you will, honey,” Inko whispers against his hair and she hopes Izuku knows it stands for more than his oversight today.

She gets another hug from her son before he’s leaving for his room. The curls of his hair rustle like an animal caught on a bush and Inko has to slap her mouth before a laugh escapes. She knows that means Cthulhu has left with Izuku and the rest of her home is safe for her sanity.

On the kitchen counter Inko finds a message and this time she doesn’t bother covering the laugh that bubbles up from her throat. In big misshapen letters made from raw pasta reads SORRY. She laughs again, not because Cthulhu’s apology is funny, but because right next to it, neatly organized, are the ingredients to make peach daifuku, Cthulhu’s favorite. Absolutely shameless.

Inko smiles. Cthulhu did put away the new groceries and Izuku has been working very hard; maybe her kids deserve a reward.

(Inko’s long realized that she does, in fact, have two children living with her. It doesn't matter that Cthulhu is as old as earth; if he's actively involved in the same shenanigans as a thirteen year old, then he's getting treated the same).

On an especially bad day, when the hurt from his classmates flares up and lights him wholly on fire, Izuku goes directly to his room and cocoons himself in his softest blankets and favorite All Might plushie. He sniffs as he squeezes the plushie against his chest and a tinny voice comes out, “I am here.”

He squeezes again. “I am here”.

And again. And again. And again.

Today, it doesn’t help. Today, the hurt runs deeper, lodging viciously in the little cracks of his heart that he pretends aren’t there. It grows harsh thorns that threaten to pry apart the careful seams he’s sewed around the worst of it.

Desperately, he squeezes again.

“I am here,” the All Might plushie says, robotic and impersonal. Cold.

Izuku doesn’t know how long he’s been crying when Cthulhu gently curls one of his tentacles around him, the very tip of it patting his hair with the same rhythm Izuku’s seen his most awkward classmates use when trying to comfort someone, usually coupled with a “there, there.”

Cthulhu doesn’t say there, there but Izuku can feel it and it makes him break a tiny smile between sobs.

Izuku has no idea how to feel about his mother and Cthulhu bonding over the fact that they both love to gossip. Inko would sometimes come back from an errand with a manic gleam in her eyes and, as she’s setting whatever it is she went out for on the kitchen table, she would ask him if Cthulhu was with him because he would not believe what she just found out about Kinomoto-san’s husband.

And Izuku would knock on his door, yell at Cthulhu that his mother wanted to tell him about Kinomoto-san and Cthulhu would rise out of the dancing darkness like an overeager puppy who just smelled its favorite treats and tell him to ask her if Kinomoto-san is the young model with a little boy and the newborn little girl.

“Yes, she is!” Inko says as she turns on the kettle. “Oh, Daidouji-san showed me photos of them and the kids are so cute.”

Izuku sighs. “Cthulhu-san wants to know about Kinomoto-san’s husband.”

“Oh, ohhh! You are not going to believe it,” Inko is looking at him but Izuku knows she’s not actually talking to him. “He used to be her high school teacher.”

Izuku blinks. “Cthulhu-san says master-apprentice relationships are quite common, so there's no reason for him not to believe it.”

What follows is a long, if fascinating because Izuku had never thought about it, lecture on power dynamics and grooming.

When his mother is done, she looks at him with the kind of contemplative look that immediately makes Izuku stand up straighter, ready to flee. Then Inko beams him a sunny, bright smile that reeks of insincerity and mischievousness.

“We haven’t talked yet, haven’t we?”

There’s alarms going off wild in Izuku’s head and he doesn’t know why. “Uh-umm… haven’t, umm, haven’t we been talking, as in, umm, right now?”

Inko claps her hands, delighted.

“Not regular talk, I mean The Talk.”

Izuku gulps. “Umm… what?”

“Yes, I think you’re old enough now. Let’s Talk, honey.”

What follows is a long, incredibly embarrassing and mortifying lecture on sex ed. Maybe Izuku is not okay with his mother and Cthulhu being friends. Clearly, he’s rubbing off on her in the absolute worst ways.

Cthulhu keeps raging any time he sees singed clothes on Izuku and Izuku keeps refusing to let him have a go at the world, refuses even to let himself have a go at the world.

“Punching kacchan is wrong,” Izuku says from where he’s perched on the log above the tiny stream. He kicks his legs just to do something with them and Cthulhu grumbles a question. “I don’t want to hurt him! I want to be a hero.”

Cthulhu flicks one of Izuku’s ear and quickly withdraws it before Izuku can slap it away but not before he tries to make a point. Izuku frowns. “if I hurt him because he's acting like a criminal then I'm touching vigilante territory.”

Cthulhu sends a whisper crawling behind Izuku’s neck to nest and die inside his other ear. Izuku looks positively scandalized. “If I'm caught there goes my chances to make it into UA!”

A compromise must be made, then.

“P-prank?”

Izuku stares down into his reflection, contemplative. “Mmh... I guess it's not vigilante activity if all I do is strictly a prank.”

His reflection grows green tentacles and the image distorts into indescribable horrors. Izuku gasps and mimes throwing his shoe at it. “I’m not gonna break his mind!” The indescribable horrors get diluted into good old body horror and when Izuku takes off his other shoe, they get further watered down into something that vaguely resembles a run of the mill mild nightmare. Izuku hums and puts on both shoes. “ ...maybe just a little.”

Izuku snorts and he bends backwards to crack his back. He’s sporting a slightly manic grin when he finally gives in. “Yeah, I guess you’re right - it's just a prank, right?”

As much as Cthulhu would prefer otherwise, Izuku only sparingly pranks his classmates. It's not safe, he says, for Cthulhu to come out at school, where he’s surrounded by so many kids who sometimes pay too much attention to him.

Izuku doesn’t lock the door, though. Which is why, when the kid sitting next to him calls him useless under his breath, he feels one of Cthulhu’s tentacles crawl through his hair and he sees his classmate’s pencil bag open wide like a mouth and a pink, wet tongue slither out to lick the boy’s hand.

The boy shrieks and when everyone’s heads turn to him, the pencil bag has nothing extraordinary about it. The boy swears up and down that it really did lick him and he’s sent to the infirmary.

When a girl very purposely bumps into Izuku and makes him drop his books, the beads of her bracelets turn into goat-like eyes that look at her like delectable prey.  Another boy laughs at him and when the boy goes to open his schoolbag he’s greeted with a nightmarish void that has him crying out in fear.

It’s only when a teacher suffers through the same that the school seems to realize someone is using their quirk to bully the school body and launches an investigation that goes nowhere. The whole thing pretty much gets shoved under a rag.

Izuku catches Kacchan looking at him with a weird expression on his face but it’s not enough for him to stop. In fact, he doesn't stop at pranking kids. Izuku is cornered by three thugs when he stays out a bit too late and Izuku shouts at the door he’s instinctively locked, loud enough to ensure he can be heard through the angry hammering, can you prank them?

Silence answers him, then a single, controlled knock.

Izuku unlocks the door.

Everyone goes home without physical injuries and Izuku gets ideas.

Indeed, he doesn’t stop at pranking kids.

Izuku is studying a paper on methodological behaviorism when there’s a knock at his door.

"Izuku, honey, is Cthulhu-san there? I made peach daifuku."

“One second mom!” He rushes to hide his notes and Cthulhu vanishes into his hair.

The bedroom door opens a moment later and his mother walks in, her eyes glance at the spot on the floor beside his bed that is twisted up, as if a giant hand had pinched that area. Her lips twitch up in a smile and her eyes crinkle with amusement as she places the tray on Izuku’s desk.

"How’s that thing he’s got going on with Nyarlathotep? Are they still not speaking to each other?"

Izuku snorts. “Cthulhu-san has decided a prank war is necessary so no, they’re still not speaking to each other.”

Inko settles on his bed, dessert in hand. “Really? What did he do?”

“It’s so petty, mom.” Izuku grabs a daifuku and unceremoniously drops it upon his head, where it promptly disappears among his curls as if swallowed. “He says otherwise but it’s all lies.”

His mother laughs and Izuku spends a blissful evening acting as a pseudo-translator between an elder god and his mother.

Endpoint is a small-time villain who’s been active around Fujiko-san’s daughter's workplace. Izuku is at her stationery store and the poor woman breaks down in sobs when Izuku sees her pale, dark-eyed face and asks her if she is alright. EndPoint is a thief and so far no one has been able to catch them because they can permanently erase the last memories of their victims and witnesses. By last, meaning, from the last minutes to the last years, and it either is random or Endpoint is just choosing to delete an arbitrary length of time.

Last night they hit a coworker of Fujiko-san’s daughter and the poor man forgot two years.

“He has a toddler,” Fujiko-san hiccups, “and now he will never remember his son’s first steps, so many first times lost.”

Izuku leaves the shop with a determined glint in his eyes. He knocks on his door and calls into the darkness.

“Cthulhu-san?”

The darkness stills its lazy swirling for a moment, then it trembles and shimmers and bubbles up like boiling water.

From under his hair he feels a tentacle slither down his spine and poke his back in greeting. He gets a grumbled question spoken directly into his mind. Izuku’s grin is full of teeth.

“Would you like to prank someone tonight?”

Come next morning, a ragged-looking Endpoint will stagger into a police station with a face devoid of blood and wild, nervous eyes. Upon interrogation, all Endpoint will say after confessing is: “The green is everywhere. There’s no escaping the green.”

Nothing else will be extracted from the villain and the case will be closed, the file sent to one Eraserhead who has taken it upon himself to investigate the curious cases of traumatized villains surrendering themselves.

The morning dawns gray and cloudy on the day Izuku turns fourteen years old. He opens his eyes and has to immediately do the reality check he always does when he feels like he wakes up but the world around him still looks like something out of a dreamscape. It’s way more often the work of the elder god who likes to mess with his reality than a lucid dream, but it never hurts to confirm.

Today, the warped walls with his room filled with warm, dimmed colorful lights is a reality. It’s pretty. Izuku yawns as he puts on pajama pants and as he leaves his bedroom the lights blink and dance. From the moment when he touches his door, the lights brighten and explode in a ripple of three extremely thematic colors. Izuku can’t help but smile wide.

His whole house is filled with swirling colors, so bright as to be nearly eye-searing, all blues and reds and yellows. He steps onto the living room and the colors twist into words, the light catching on them giving them an iridescent hue that almost looks like rainbow glitter.

HAPPY BIRTHDAY, is what they say.

He beams, eyes tearing up, and practically runs to the kitchen, where he promptly freezes at the sight before him.

There’s his mother, beaming at his general direction with her brightest smile. She has a thick blindfold covering her eyes because seated in front of her at the table, which, by the way, has presents and an All Might cake, is Cthulhu. He’s shrank himself enough to only almost touch the ceiling with his head, his wings are completely ignoring the very physical and sturdy architecture of the kitchen, his knees towering over the table. He looks like a ridiculously tall adult sitting at a child-sized table and Izuku laughs.

His mother claps happily, she’s not exactly looking in his direction but a beaming smile blooms wide on her lips. “Surprise, honey! Happy birthday! This was Cthulhu-san’s idea!”

That brings Izuku up short.

“What? Did you speak to each other? How? And you’re okay, mom?”

His mother giggles and gestures pointedly in her crime partner’s direction. Cthulhu takes a device which looks dwarfed on his hands, until he sprouts a human-sized arm from one of his fingers so the fingers on said human-sized hand can type something on it, painstakingly slow, one key at a time.

From the device comes an electronic crackle, then: To him that will, ways are not wanting.

The voice is tinny and robotic and Izuku gapes. He’s speechless for so long that his mother laughs again, correctly reading into his shocked silence.

“I told you we were going to break him,” says his mother, her head turned towards Cthulhu, whose face tentacles tremble in what is undoubtedly silent laughter. Even though Cthulhu has always been careful not to accidentally hurt his mother, the sight of the old god holding back from expressing his mirth still touches Izuku.

He looks at them both. At his mother grinning at him, at Cthulhu making himself fit his kitchen, at the otherworldly decorations along with the earthly streamers and cake and Izuku can’t help it; he cries and he hurries to hug his two most precious people in the world, babbling all the words of gratitude and appreciation amidst his tears.

Later, much, much later, after he’s eaten so much cake and ice cream and the delicious food his mom cooked for him; when he’s laying on his bed, thinking back on the day and how it’s been the best birthday he’s ever had, he asks Cthulhu why he doesn’t text his mother more often.

He hears some struggling and something clattering to the floor, then the slow click clack of keys being pressed for a long, long time. From the shadows on the corner of his room, he hears the same tinny, robotic voice from that morning: effort.

Izuku laughs and the smile remains on his lips when he finally succumbs to sleep.

Eraserhead is tired. Tired of life, of teaching children who think nothing can hurt them, then staking out adults who think nothing can hurt them. Eraserhead is, on this specific night, crouching beside the dead and pungent remains of some small animal, tired of shady people always choosing the dirtiest and smelliest alleys to do their shady transactions in.

He's not staking some shady transaction tonight, though. Tonight he's investigating the very peculiar and curious case of some small fry getting scared out of their wits enough to surrender themselves to the apparently sweet relief of imprisonment.

It makes no sense whatsoever and it vexes Eraserhead immensely. There are no reports of damages or signs of struggle; what little injuries the criminals had on them were either self-inflicted or the kind of insignificant scratches one gets when accidentally running into something.

As far as he knows, he's dealing with an illusion type quirk, one powerful enough to involve not just sight, but all five senses. Almost all of the reports informed of the victims being able to touch, smell and even taste the nightmarish illusions. Those are never the same, which makes sense, given how the victims' accounts clearly indicate they are specifically tailored to target both the victim's and their quirk's weakness. The only thing in common seems to be a green theme. A lot of green, judging by all the nonsensical mumbling about how it's everywhere and inescapable.

The attacks are concentrated on a pretty short range, which indicates whoever is behind them has issues regarding either mobility or transportation. There's been five cases so far, all spread out from each other in a non-discernible pattern. It would look opportunistic rather than targeted, were it not for the fact the illusions are specifically fabricated with their victim in mind. It could be that the quirk itself can read its victims weaknesses and it is an opportunistic amateur vigilante that Eraserhead is dealing with; it could also be a less amateur vigilante with a good information net and decent analytical skills.

His musings get interrupted when he catches sight of a dark figure jumping from rooftop to rooftop, landing on well executed rolls. It’s the child again, isn’t it?

This is the third time Eraserhead has seen this particular kid. A child walking alone at night is a worrying if not an unsurprising sight; this kid looks fit and well fed, which means he most likely has a roof over his head and he wouldn’t have been marked as someone of interest if it weren’t for two things.

One, his green hair, which can only be saved from sounding like a bonker reason by grace of thing two; both times he spotted the child around the locations where the victims would later state the attack took place.

This is the first time Eraserhead sees him moving above ground, though. Despite himself, he’s impressed by his dexterity and he takes off after him at a stealthy pace. Kid’s got the tells of the self-taught and the confidence of someone who knows what they’re doing. Well, Eraserhead hopes it’s confidence and not arrogance as he sees the kid vault over a breach between buildings that’s a bit too wide and oh, shit, the kid’s not gonna make it and Eraserhead is too far away for his capture weapon to reach him in time.

His vision whites out and a brief pulse of pain unlike anything he’s ever felt rams through his eyes and into his brain. There are things crawling under the skin of his cheekbones, eating through the bones and he needs to take them. Out. Now.

It’s with great heaving pants that Eraserhead comes to, hands clawed less than an inch away from his face and the horrifying realization that he was going to rake his own face. What the fuck.

Has he been attacked by the same person who targeted the villains? Because if so Eraserhead could sure as hell sympathize with the desire to surrender because shit, it’d been only a few seconds and it was terrifying. Yeah, no shit, he could see how traumatizing a longer exposure of that (something tailor made) must be. He whips his head up, still heavy of breath, surveilling his surroundings.

Nothing. No movement, no out of place sounds. He’s curled up alone on this rooftop-

It’s at this point that he remembers that his suspect was about to go splat.  He staggers up, closes the distance to the edge as quick as he can just in time to see the child take a fire escape three buildings ahead. Guess he did make the jump, after all.

With another searching glance around him and the kind of sigh that carries the same weight as a curse, he lets the kid get away. He needs to attempt to find whoever attacked him; with a little bit of luck they’re still close and Eraserhead will find them.

Unsurprisingly, given his luck, Eraserhead doesn’t find them. Who he finds the next night when he goes on patrolling is the kid, again.

Against all odds, the kid lands on a roll right next to where Eraserhead has been crouching, using the shadows from a water tank to hide himself. This time he doesn’t take any chances and his capture weapon flies to wrap around the kid, who yelps in surprise.

He tries, really, honestly tries to interrogate the kid (Midoriya Izuku, that’s what he said his name was) but it’s damn hard when he’s being looked at with the most starstruck, starry-eyed puppy look he’s ever been given in the history of his life. Not only that but this Midoriya actually recognized him on the spot, blurting out his hero name at the sight of him.

This kid was happy to be wrapped in his scarf, for god’s sake, acting like it was the highlight of his life.

So yes, Eraserhead does try to interrogate him, see what reason he could have to be at some of the attack locations, except as soon as he starts this kid just goes://

“I’m not a vigilante.”

Okay, Eraserhead hasn’t said anything about vigilantism but he’s not about to shut down someone who is careening straight into their grave; so he merely raises a brow, giving Midoriya the unimpressed look that always makes the toughest students think twice about something and parrots the statement back, with a voice as flat as he can physically make it.

“You’re not a vigilante.”

“Yes! Quirk restrictions laws prohibit the use of quirks to commit heroic deeds without a prohero license, defining an individual who does so a vigilante; given that the nature of my quirk prevents me from misusing it as it has no direct effect on the world or any person at all, pretty useless, actually, I, by legal definition, cannot be labeled a vigilante.”

Eraserhead stares at the audacity of this kid. He both likes and dislikes the smart ones who can argue a case around loopholes not just because they’re clever but because they bother to do their homework.

Still.

“So you admit to acting in ways that can be perceived as vigilantism while taking advantage of a technicality.”

Midoriya’s eyes go as big as saucers when he realizes his blunder. “Umm. Ummm.”

“What’s your quirk, then?”

Midoriya’s face positively lightens up and gives him a smile that makes Eraserhead narrow his eyes because that smile borders dangerously on the side of mischievous. “I can keep one specific door locked!”

A blink. That. That was not what Eraserhead was expecting. With all the roof jumping and sneaking and self-incriminating talk about not vigilantism, Eraserhead was anticipating something less… tame. He takes an appraisal look of the kid, experience has honed his instincts and his gut is telling him Midoriya isn’t lying but that doesn’t mean he’s telling the full truth.

“A specific door?”

“Yup! A door pretty much designated at birth, and I can’t lock or unlock any other door but that one.”

There is definitely something not being said here. Eraserhead sighs and unwinds his capture weapon from the kid, settling it again loosely around his own neck. One look at Midoriya’s face and you would think he stole his birthday presents. Weird kid, Eraserhead can already tell he’s going to be a Problem.

Time to hit the quirk registry, see what else he can find. One more thing before he leaves, though. There’s a high chance someone like Midoriya wants to be a hero, and even if he doesn’t there’s something about what Midoriya said that doesn’t sit well with him.

“There are no useless quirks, not for a creative mind. Now go home and sleep, kid, this is a school night.”

Izuku didn’t get much sleep that night, too high strung from having had a talk with Eraserhead (!). Not that it matters because all the sleeping in the world couldn’t have improved the following morning. School is simply not good that day; some of his classmates found out the teachers will be handing out high school applications and the worst of them have been cruelly needling Izuku about his very public desire to go to UA.

Then the teachers do the actual handing out and Izuku’s teacher scoffs at him. What could he hope to accomplish with such a weak, useless quirk? That is, his teacher adds with a sneer, if your quirk actually does exist. 

He stays back when school ends, the cruel words still ringing in his ears and cracking his self-worth as they bounce, repeating in a loop, inside his mind. They are right, after all. His quirk is useless. Eraserhead has to be wrong because everything he’s done is due to Cthulhu-san taking pity on him and occasionally lending him his otherworldly capabilities. Could he really be a hero like that?

Izuku tunes out Cthulhu’s attempt at cheering him up as he drags himself home. He’s walking through an underpass when he’s suddenly attacked.

As the slime villain chokes him he slams the gate, closing the lock with all his might. Izuku would cry out at the agonizing starburst of pain that threatens to split his head open, but he is too busy trying to grasp air to do so. He thought, he really did, that when Kacchan burned him, he knew what it was like to have Cthulhu try to break free. He’s now realizing he was wrong, wrong, wrong, wrong. This is an elder god pushing all of his unearthly power against Izuku’s iron will and it hurts. Cthulhu is pounding on the gate, demanding to be let out and Izuku can feel the homey feel of the door’s cold turn freezing, murderous. He can’t see it but he thinks he feels the frame of the door give a little and the agony of it makes him open his mouth to shriek.

Art by IhaveHatsInMyPants

The villain forces one of their slimy appendages down Izuku’s throat. He cannot breathe. He cannot think. It’s too much, he can’t do this, he’s crying, he’s going to die and he doesn’t want to but he can’t let Cthulhu out. Cthulhu is too protective, he can hear it in the way the elder god is roaring with devastating desperation, that this time he wouldn't stop at pranking, he would destroy this person, completely annihilate them. And Izuku can't let that happen, not even to a villain.

He needs to do something soon, before he loses consciousness and there's nothing keeping Cthulhu out. Darkness is encroaching at the corner of his eyes and he can feel his hold on the lock start to weaken, but then a hand is pulling him abruptly away from the slime and Izuku can breathe again, the lock yet again secure.

In the span of 20 minutes, Izuku's life is both saved and destroyed.

"My quirk allows me to keep one specific door closed, can I be a hero with a quirk like that?"

"I'm sorry, young man, but I'm afraid a quirk like that is not suited for heroics. Why don't you try police work?"

And Izuku's hero leaves the building, shattered dreams and dangerous secrets left in his wake. Izuku sniffs, trying very hard not to cry but not even his strong will has ever been capable of stopping the infamous Midoriya tears.

He feels something tug at his backpack, and he hears the swift snip of something that has been ripped. From Cthulhu's claw dangles his All Might keychain and Izuku is both feeling immensely fond and sorta horrified when Cthulhu turns it into a bubbling mess of deformed plastic.

A question forms in his mind and Izuku shakes his head, a sad little smile upon his lips.

"I'm sorry, Cthulhu-san, but you can't do the same to the real All Might."

Another intrusive thought.

"Okay, fair, but just because you maybe can, doesn't mean you should."

Izuku sighs.

"I’m not pranking All Might, Cthulhu-san."

He feels more than hears Cthulhu grumble and very pointedly closing the door on his own, the god’s way of expressing his disapproval. His dramatic departure drags an unexpected snort out of Izuku, his heart warmed by the old god’s particular brand of care.

It’s not enough to erase the sorrow that clings to him after All Might’s words and Izuku starts the trek back home with heavy feet.

Fate is certainly not feeling kind enough today, though, because Izuku encounters the slime villain again.

It’s later, much, much later, when the sun is starting to set that the weight of what he did is finally crashing down on Izuku. Cthulhu is back with him again and has been ranting and raging for an hour straight because the old god literally left Izuku for less than an hour and Izuku was in another near-death situation again and he found out not from Izuku himself, but from a random TV shop they passed that was streaming the incident.

Izuku is inclined to agree that what he did was too reckless and dangerous and he’s having a hard time trying to analyze the instinct that drove him to do it. He’s thinking so hard, in fact, that he fails to notice All Might in front of him.

He does notice his idol offering his own power, though, and as he bawls because, yes, yes, he wants it, he wants to be a hero more than he's ever wanted anything else and with All Might’s quirk he can. He’d already decided to try for his dream with everything he’s got but when before it felt as if he was trudging through an everlasting darkness with naught but a borrowed match, now he can walk with a sun on his hands. He won’t disappoint All Might. He won’t.

“There is just one thing, young Midoriya,” All Might’s face is serious and Izuku tries his best to reign in his tears to pay attention. “The knowledge of my quirk is too dangerous, you must keep it a secret.”

Izuku stares, gulps and avoids All Might’s gaze. He can feel Cthulhu laugh maliciously and knows All Might has just damned himself. “Um-umm, that, I mean, that-that is not possible All Might.” Izuku sighs the kind of sigh that all long suffering individuals know by heart. “My mom is going to know.”

Even though he’s not looking at his hero, Izuku can nonetheless feel his disappointment.

“Young man, you can’t-”

“No! “ Izuku rushes to correct him, “I mean, I can keep it a secret but Cthulhu-san will tell her just because you said not to. He loves to gossip with my mom.”

All Might just stares. “Excuse me, but who is Cthulhu?”

All Might knows there’s quirks and then there’s quirks. He knows how varied and weird and how reality-breaking they can be. He knows how they can be used for absolutely wondrous, wonderful things and he’s experienced first hand how twisted and ugly they can be when abused.

But those are quirks. It’s one thing entirely to know about quirks that can do the impossible, even by quirk standards, and another thing entirely to accept the existence of impossible beings capable of equally impossible things.

More to the point, it’s really, really hard to accept that the tiny boy he’s chosen as his successor, the same one who cried when One for All was offered and looks up at him with such hopeful eyes, has a door inside him that leads to chaos and impossibility.

All Might’s not sure he can accept it, but he can accept an invitation to the Midoriya’s home for dinner and a talk, since the young Midoriya insisted a talk with his mother was absolutely, 100% necessary.

The Midoriya house is cozy and homey. It would be, All Might thinks as he tries his hardest not to notice the way the chair he’s just sat down on has turned into an odd-feeling bean chair, very nice if besides cozy and homey it were welcoming as well. The bean chair squelches when he fidgets; and when he makes the mistake of touching it with his bare hand, he realizes it’s damp and too warm.

All Might can’t help but fidget a little more, distressed and uncomfortable, and the bean chair starts moving slowly up and down, not unlike breathing.

Young Midoriya notices his discomfort because his eyes widen and he visibly frets. “Cthulhu-san! Please don't bully All Might.”

It’s fascinating, from a purely objective angle, the way young Midoriya’s face scrunches up until his eyes close and he looks like he just heard something painful. He sighs and when he opens his eyes, they’re full of contrition. “I’m sorry, All Might, he doesn't think very highly of you.”

Young Midoriya flinches. “I'm not saying that!” Then yelps and one of his hands goes to cover his right ear. “Oww!  No! I will lock the door!”

All Might watches nervously, as shadows detach from beneath furniture to converge into a swirling spot between young Midoriya and himself, sinking through the floor like water down a drain. The floor ripples and it rises like magma out of an angry volcano, bubbling around itself until it’s shaped into a  figurine of himself dressed up as a clown. It’s… an incredibly good and realistic rendition.

Clearly, All Might thinks, he is far from welcomed here. Maybe he should try another time? He attempts to stand up without touching the damp bean chair, which he can now see it’s actually wet enough to be glistening. “ ...this might not be the best time.”

“Cthulhu-san,” young Midoriya’s mother, Inko, sharply calls out as she comes out of the kitchen, snack tray in her hands. She intones the name of something that shouldn’t be like she’s scolding an unruly child. “If you do not stop being rude to our guest you will not have daifuku for the rest of the year.”

All Might watches, eyes wide with morbid fascination, as his chair turns back to mostly normal, just a little bit too organic to be one hundred percent comfortable. Did she just-? Oh, god, she did.

“Good, thank you, Cthulhu-san. Well,” and now this woman is turning to him, casually, like she hasn’t just successfully ordered an elder god to behave. “What was it you wanted to discuss?”

All Might may be a little bit apprehensive now, because every new member he meets of this family is scarier than the last. Dare he wonder who’s the father? He clears his throat, then his mind and proceeds to explain the bare bones of what he’s offered Izuku.

Inko is, in two words, not happy. When she finally speaks, after a full minute of dead silence, her voice is the kind of cold that promises swift death.

“So let me get this straight: you offered a life-altering body modification to an underage child, am I right? And not only that you wanted to swear him to secrecy, to keep such a.. a.. condition that will stay with him for the rest of his life? What was he supposed to say when I noticed the changes? That he suddenly, out of the blue, developed an all new quirk? Or were you hoping for me to be so neglectful as to not notice an All Might-level kind of power up on my own son? Did you properly inform him of everything carrying your quirk conveys? Will it change him physically? Will his own quirk coexist peacefully with yours? Or were you banking on his hero worship of you to follow you blindly?”

All Might’s gaping at her and, from the corner of his eye, he can see young Midoriya is doing so as well. Her concerns are not unfounded and he feels chastised. He apologizes and tries his best to explain anew.

Inko is so far past unhappy when she learns that young Midoriya has to buff up his body before receiving One for All because it could destroy him that she kicks him out.

It takes days before All Might gets a text from young Midoriya that he’s convinced his mother to give him another chance. Then it takes almost three weeks for the combined efforts of All Might and Midoriya to convince Inko to let them try.

It’s almost a month before Eraserhead sees Midoriya again. He’d gone through the records in the meantime, only to find that everything Midoriya told him is true. His quirk is quite literally a door, it just so happens that the door he can lock is in a rather unusual place.

He finds the kid at the very start of his patrol, hunkered down behind a half-filled dumpster, notebook in hand and backpack carefully placed against the cleaner wall. Eraserhead moves silently, advancing along shadows and crouching closer with every bursting of noise and music from the backdoor a few yards away. He’s so close now he can hear Midoriya's muttering. Eraserhead stops, cocks his head, listening.

“...violent flinch when neon signs went on but no reaction to dim automatic lights going on, both lit up space about the same. Sensitivity to bright colors or mere surprise? Avoided the alley with cats. Cat avoidance is, in fact, strong enough to cross streets and change sidewalks, meaning we can assume a phobia.” Midoriya pauses for a bit then snorts. “I’m not sure a neon light in the shape of a cat would make the cut but remember the glow in the dark rabbits? That but with cats.”

Ah, so it appears it’s not mumbling but an actual conversation with someone. A very damning exchange. So Eraserhead's first hunch was right and Midoriya truly is involved in the attacks. He plans on waiting until the communication is dropped but the kid’s hair moves unnaturally, not unlike seaweed underwater, and then the Midoriya is sharply turning back to make eye contact with him.

Eraserhead sees a scratch on Midoriya’s cheek, sees his bright green eyes above and then watches as a dozen brighter, greener eyes blink open at the ends of the kid’s hair, green all around, so much green, and then Eraserhead is seeing too much. He sees the world in angles and numbers and equations. Sees the streetlight break down to wavelengths. Sees the brick and mortar of the wall as clusters of atoms that move like a busy anthill. Sees the trash peeking out of the dumpster disintegrate into water and gasses whose chemical formulas he can taste. A bright pink CO2 floats through the air like a bubble and pops and fizzes out when it touches his nose.

It ends before he can go through the thought process necessary to activate erasure. He doesn’t realize he’s rocking his body, a low keening coming out of his mouth, until small hands grasp at his shoulders.

“...oh my god, oh my god, I’m sorry, I’m so sorry...”

Falling back on basic breathing exercises, Eraserhead tunes out Midoriya’s frantic apologies and concentrates on bringing down his deafening heartbeat.

Once he feels calmer he rasps out: “What. Happened.”

Midoriya’s voice raises to an even higher pitch, “I’m sorry! We-I thought I was getting mugged again!”

That makes him perk up, worry creasing his brows. “You were mugged?”

"I got cornered like an hour ago by some guys and they were gonna take the new All Might model with joints and-”

“...they were going after your All Might merch?”

“Well, uhm, not-not the merch per se but my backpack? Where… I… have it?”

“...”

“A-and, um, they roughed me up a bit so I asked Cthu- … a friend to help and he stopped them.”

Eraserhead eyes him critically but other than the scratch on his cheek, nothing else seems amiss but might as well confirm. “You okay, then?”

Midoriya nods with enough force to make his hair bounce all over the place, which reminds Eraserhead of something he was certain he saw before everything went nuts. He’s certain now that Midoriya isn’t alone, so he subtly shifts his weight for better mobility and moves his hand as if to scratch his neck so he can place it right next to his capture weapon.

“Good, so would this friend of yours be the same one who’s sent traumatized thugs to the police station?”

Midoriya’s deer in headlights look says enough.

“And would this friend have anything to do with eyes on your hair? Because as far as I recall, that is not part of your quirk.”

He can actually see Midoriya mouth the words ‘oh fuck' and he gives him his patented don't-make-me-wait glare. "Spill, kid."

Twenty minutes later and he's thoroughly regretting having ever asked.

"You said your quirk was to keep one very specific door closed," he states and Midoriya must sense something because he nods hesitantly. "I assumed, since you didn't bother to specify, that it was a normal door, not a door that can be more aptly described as a portal to hell."

Midoriya fidgets, anxiously playing with his fingers. "It'smoreofacosmicdimension-"

That is so like the bullshit his students pull when they try to outsmart him that without thinking he glares and activates his quirk to bring order, only to find himself curled up in fetal position, afterimages of brightly lit green shadows still present on his vision.

“What.”

He used Erasure on the kid and Midoriya’s quirk was not erased, how? Midoriya is ahead of him, the kid has obviously thought about his quirk a lot, if his excited babbling is anything to go by.

“Oh, wow, I think we can take this as confirmation that my quirk is a mutation plus emitter hybrid type. It’s been established that I am the door, which is the mutation type, and the lock is the emitter component, given that I can manipulate it at will. If I lose consciousness I fail to keep the door locked; the mutation part can’t be erased as demonstrated right now by Eraserhead’s use of Erasure, only the lock disappears which renders the door automatically open and Cthulhu-san free reign to come out.” Midoriya takes a deep breath and beams at him with the force of a thousand suns. “Thank you so much, Eraserhead!”

This kid. Honestly. That was a nice bit of analytical reasoning, though. He stares at Midoriya in silence for too long, trying to come to terms with the fact that Midoriya cannot, in fact, control Cthulhu. Indeed, everything  is made worse by that little tidbit that Midoriya’s hold on the lock disappears with his consciousness. Giving Cthulhu free reign to come out. Cthulhu, who has attacked him twice just today. Midoriya is a nightmare.

“Is Cthulhu in the habit of attacking people?”

“Ah- he’s not actually attacking people. It’s just that his, umm, racial characteristics make it hard for our minds to comprehend the sight of him and the brain translates the visual stimulus into, umm, something like temporary madness?”

Scratch that nightmare bit, Midoriya is a walking time bomb.

“And, I mean, well, you did use your quirk on me and Cthulhu-san is very protective; I always lock the door if I think I'm gonna be in danger, but with Erasure... I'm sorry, Cthulhu-san doesn't really like authority figures.”

Eraserhead pinches the bridges of his nose and sighs. The ground gives the impression of utter innocence when he looks at it but now he knows better. He sounds dejected when he asks: "Is he here right now?"

To answer him, Midoriya's shadow detaches from his body and creeps out to situate itself right next to his own, standing close like hated enemies one second away from mutual stabbing.

“...hello, I guess.”

The shadow waves back and Eraserhead wonders what is his life.

“Oh, I think he may like you, he told me to tell you hello.”

Eraserhead refuses to acknowledge that. Absolutely no contemplating that he might be in an ancient, otherworldly creature’s good graces. Then he remembers the quirk registry and, specifically, how there’s no mention at all of what lies beyond the door. So he asks, he briefly wonders if he’ll regret the answer this time as well.

“Well, I’m a door, right? But I’m not the only door, not even the only way from Cthulhu-san’s dimension to ours; he says there are summoning rituals that can force open a temporal portal between our worlds, then there are spaces, like liminal-kinda spaces, where circumstances aligned right to make a natural door, and occasionally, a living being will be born with a door inside. Like me.”

Cold sweat rolls down his spine. Is Midoriya telling him that his world is connected with an actual hellish dimension, home to even more hellish beings, and that those beings could just cross into their world? Anytime? At will? Would something like Erasure even work for someone, something, that was not ruled by the laws of their world?

“We, by which I mean my mom and I, we think the less people that know about Cthulhu-san, the better. She thinks I could be targeted by supervillains who would want Cthulhu-san on a leash, or by shady people who might want to experiment on me, trying to go over to Cthulhu-san’s dimension.”

“But your quirk can’t control Cthulhu, he has his own agency and if he’s free to reach any of the other doors…”

Eraserhead can now see the rationale, with what he’s learned tonight he can predict what Midoriya is going to say next. He hates that he thinks they’re right.

“Exactly. Cthulhu-san has said before that if I'm hurt because of my link to him he’ll come out of the closest open gate and bring hell with him, so my mom thought it was safer if we kept him in secret so that no one could get ideas to lock me up or kill me since my well being has no bearing whatsoever on whether Cthulhu-san has access to our world. I just happen to be a convenient pathway, one of many.”

Eraserhead thinks of the rumors he’s heard on the underground, about people going missing and the whispers of certain experiments. The tightly reigned murmurs about the hero commission. “I think your mother was right.”

Midoriya nods and, on the ground, his shadow keeps on nodding long after he’s stopped. Gods. He can’t even tell Hizashi about this, can he? He’ll think he’s gone off his rockets. This is something that must be experienced to be believed. It’s easy to accept the weirdest, more powered up quirks when you grew up hearing about them, about the possibility of them. It’s another thing entirely to accept something which you previously thought was mere fiction.

“Right?” He must have thought aloud. “I think Lovecraft might have been a door, too. Cthulhu-san says organic, living doors are rare but I’m nowhere near the first.”

Laughter and jubilant shrieking abruptly erupts and Eraserhead remembers they’re still hiding behind a dumpster. Some lights flicker overhead and he also recalls how he found Midoriya. He knows the answer but he still needs to ask.

“Do you want to be a hero?” Please say no, Eraserhead pleads to any god that may be merciful enough to listen to him, even though he knows it’s futile.

“Yes, I wanna go to UA!”

Of course the kid with an eldritch best friend wants to attend UA. He swallows back a groan because he knows, without the slightest doubt, that Nedzu will put this kid in his class. Might as well start to lend a hand to future Aizawa by making his job easier now.

“...give me your phone.”

Midoriya blinks owlishly at him, then hands over his phone without a word. Eraserhead takes it, types his phone number in it then saves it.

“That’s my number. I’m trusting you to use it responsibly and to call me if you need help; I’m a teacher at UA so I can give you some pointers on how to start your training for the entrance exam.”

Midoriya’s face brightens impossibly when he says: “I already have a teacher! The best teacher I could hope for!”

Eraserhead nods, that’s good, very good but.

“Do they know about Cthulhu?”

Midoriya opens his mouth to answer but doesn’t get a chance because the concrete next to his feet liquefies and from the puddle emerges a life-sized All Might statue. Eraserhead stares at the statue and the statue stares back, then nods.

Midoriya is horrified. “Cthulhu-san what are you doing? This is supposed to be a secret!”

Wait, what? Eraserhead looks at Midoriya’s distress, at concrete All Might nodding and remembers the question he posed immediately before this. Oh, god.

“All Might is teaching you?”

All Might has no teaching qualifications, zero at all, not even experience of any meaningful kind with teens. Eraserhead has no doubt the man is an extremely effective hero, brilliant in his own might to have reached number one in the rankings and keep it for as long as he has. Yes, no doubt the man has enough heroic experience to draw from, but it’s one thing entirely to know something and a completely different beast to pass that knowledge on. This is what he doubts All Might can do, but see if Nedzu listens to him.

“All Might is a good hero, but what you need is a real teacher. Give me a call tomorrow, I want to look over what he has planned for you and I need to meet with your parents to discuss it.”

“Oh, mom will like that, she was so angry with him when she found out he wanted to train me in secret.”

“...he wanted to do what.”

He’s going to lose it, go off the rails entirely because this is crazy. “Go home, Midoriya. Don’t forget to call.”

Eraserhead stays only until he sees Midoriya disappear in the distance, then he leaves to continue his patrol. It’s four hours later that he gets a text, a long wall of text revealing things that shouldn’t be sent via unsecured chat apps. It’s a heap of bad to work with that’s made worse by the name that signs that text.

-Cthulhu (: 

Three days later UA holds a meeting with teachers of the heroic classes to discuss a matter of extreme importance. At this point they know All Might will be joining them for the next course, so his presence there is only deserving of mild surprise. The actual, real surprise comes when the number one hero deflates and both he and Nedzu explain his current health status. The meeting is to discuss the dilemma this poses and what measures to take to keep this from the students and the rest of the staff.

Aizawa, knowing thanks to one text the real situation, practices breathing exercises to keep himself from throttling the blond hero. He waits until the meeting is over, asks All Might all polite and proper for a moment in private, then leads him to the empty teachers’ lounge.

Taking just enough time to confirm the door has indeed been locked, no chance of anyone accidentally coming in and listening to sensitive information, Aizawa rounds on All Might.

“Tell me you did not offer a life-changing power up quirk to an actual, literal, unable to consent child.”

All Might’s shock would be funny, if Aizawa weren’t so angry.

“This plan is trash.”

They’re in the Midoriya’s living room; Izuku, his mother, Aizawa and All Might, that is. Izuku had had a little freak out over that this morning and his mother had been subjected to almost an hour of how amazing and unbelievable that was; and of stats and fights of each hero. Izuku would say he is calm now, but every time he looks at the heroes poring over his training plan (his! training plan! being looked over and supervised by two pro heroes! the very best pro heroes!) is enough to almost throw him over the edge again.

Right this instant, though, what he feels is incredulity at Aizawa's words. He ignores Cthulhu mocking laughter rippling down his spine because seriously? All Might’s plan? Trash? 

All Might seems to think similarly because he splutters and gapes like a fish out of water.

"That-!”

But All Might’s either protest or justification is cut short by Aizawa sharply putting up a hand, in the universal ‘wait’ gesture.

“This plan is not baAizawa deadpans, “for an adult.” Aizawa blinks, seemingly thinking of some adults in his life, and amends: “Well, a fully emotionally mature individual.”

Izuku would laugh at the almost identical sounds of outrage Cthulhu and All Might make, but he’s a little busy feeling hurt to do so.

“Young Midoriya is a perfectly capable young man,” All Might starts to make a valiant effort to defend Izuku but he’s stopped by the sound of Izuku’s mother’s glass clinking as she pointedly places it on the table.

"Aizawa never said my Izuku wasn’t capable,” she says, looking him dead in the eye, “we now my son is exceptional; he’s smart and he’s brave but no one who sneaks out at night to engage with dangerous villains and accepts offers of power without thinking it through can be called emotionally mature.”

Izuku is cringing and resolutely refusing to look his mother in the eye but he still feels the sting of those words. She was still upset about all that, then.

Aizawa doesn’t bother to hide a smirk. “We’re talking about a child with no sense of self-preservation and who ignores his own limits. The plan has to be corrected with the thought in mind of the very likely possibility that Midoriya will attempt to go beyond the agreed on plan.”

Izuku freezes, because he had thought there was no reason why he shouldn’t continue with his training by himself after his sessions with All Might were done. Eraserhead, pro hero extraordinaire, seems to cotton on to this, because the glare he levels at him is mighty indeed. Izuku gulps and pretends to count the flecks of dust on the table.

In the end, though, he gets a perfectly good training plan that has the approval of all three adults. Izuku can’t help but feel full of joyful expectation. His own particular hero training, tailored to him by two of his favorite pro heroes, starting a week from now!

Standing on the steps down to Dagobah Beach, Izuku thinks that he’s never before thought of it as imposing, but then again never before has he looked at it with the intention of actually cleaning it out. The amount of trash on the shiny sand piled up high in actual little hills is unbelievable.

Well.

He has several months to complete it. He can do this. Izuku takes a fortifying breath, scrunches up his brows with determination and takes the first step down, rolling up his sleeves.

The pile closest to him has a lot of electrodomestics in several states of deterioration; there’s an almost intact microwave missing its door, an oven so rusted over Izuku is only sure it’s an oven because there’s still the word ‘oven’ in plastic hanging onto its side. There’s actually a lot of rusted iron and the sand he thought was shining is only doing so because it’s full of glass.

Well.

Izuku’s thankful for Aizawa-san’s endless wisdom and the good, sturdy work gloves he gave him. He rolls his sleeves back down and reaches to his back pocket, where the gloves hang. He puts them on and gets to work. The small, loose stuff on the ground goes first in a bag that once unfolded turns out to be almost as tall as him.

Not far away from him a shrunk down Cthulhu is snickering while moving trash about. The beach is deserted and the trash hills hide them from view anyway, so there’s no danger of mass panic and hysteria if Cthulhu is out. The snickering turns into chortling and Izuku’s curiosity is piqued. He sneaks a peek and is immediately hit with the uncertainty of not knowing whether to laugh or cry.

Cthulhu has found a more-or-less still intact toaster with two blue plastic caps on its front and below them, a curved rip that looks too shiny and new to be anything other than caused by Cthulhu’s claws. Cthulhu has stuck the toaster on top of what is either a part of a mangled bed frame or several coat racks knotted together, surrounded this gangly monstrosity with a bleached piece of cloth and crowned the toaster with two banana peels.

It’s undoubtedly supposed to be All Might and going by Cthulhu’s gigglesnort fit, not a positive depiction of the hero. Izuku wisely decides this is not a battle that he is going to win alone and withdraws to continue with the cleaning.

The lifting and the hauling is much easier than he thought it would be, Izuku is surprised to discover and he feels Cthulhu’s laughter rumble down his back, mocking him. Izuku listens to what Cthulhu says, a small look of wonder drawing shy stars on his eyes as he looks at his hands like they hold precious treasures.

Because Cthulhu is right, isn’t he? He didn’t start his training today, he started it years ago. He took up parkour to make himself fast and flexible, took up weight lifting to make himself strong. Cthulhu used to make fun of his weak body and now Cthulhu is making fun of him for thinking himself still weak.

Izuku throws back his head and laughs and laughs and laughs, crystal clean tears rolling down his cheeks.

“I made myself strong,” he says, hiccuping.

One of Cthulhu’s green, scaly claws creeps out from beneath the hair at the nape of the neck and very lightly scratches his head. When Izuku’s tears don’t stop, Cthulhu scratches harder, insistently, until Izuku giggles and wipes his eyes with his sleeve.

He lifts the heaviest thing he has at hand and turns back to the truck.

“All Might!” Izuku yells, jogging towards the hero with the doorless microwave hoisted up high over his head. The sun shines warmly down on his hair and while the light is bright it’s nowhere near blinding as Izuku’s grin is. “Look, I’m strong!”

All Might gives him a little proud smile and two big thumbs up. “You are, my boy!”

The joy and pride and the absolute sense of accomplishment he feels crash down on him like a wave and fill him completely. Izuku thinks this feeling could carry him on forever, he feels elated and warm and euphoric to the brim. For the first time in a long, long time, Izuku feels like he’s enough.

He’ll clean this beach in no time. He feels like he could clean five of Dagobah beaches in no time.

By the time Izuku hits the five month mark, he’s cleaned more than half the trash and has had two identical discussions with Cthulhu regarding whether or not he’s ready to accept All Might’s quirk. Cthulhu seems to be convinced third’s the charm because he’s bringing it up again.

"But Cthulhu-san, you heard All Might, I'm not ready."

Izuku picks up a broken fan and starts hauling it away. He can tell by Cthulhu’s tone that he will not be convinced this time. "Cthulhu-san you can't know that."

Izuku snorts. "No, you really, really don't."

"My mom has known me for all my life and still she would not argue with a doctor about my health because the doctor is the expert," Izuku explains patiently. He points at All Might, who is looking at him with a bit of a strained expression. "All Might IS the expert."

A bit of frustration seeps into his voice, eldritch beings can be so infuriatingly stubborn sometimes. "You're not even arguing with him, you're arguing with me!"

Cthulhu huffs, crawls out into the shadows on the beach and slithers into the ocean. Where the waves gently lap at the shore, the sand shifts, boils and rises up in the shape of All Might.

Izuku slaps a hand across his face. “Not again, Cthulhu-san.”

All around the All Might sculpture, sand tentacles the diameter of All Might’s tight erupt in a violent writhing frenzy. Izuku sighs as he watches them seize an abruptly very lifelike sculpture and drag it slowly towards the ocean, the All Might rendition kicking desperately and mouth open in silent, fearful screams.

The sand dissolves in contact with the water and Izuku chances a look over his shoulder, but the real All Might has apparently decided that the heart can’t fault what the eyes can’t see because he is very pointedly not looking their way.

Izuku is so tired. “Cthulhu-san, please, I know you don’t like All Might but he’s said I’ll get his quirk when the beach is clean, and look! I’m almost done!”

He gets no reply; not a peep, not a sound, not even angry muttering. Nothing. It makes Izuku very, very nervous.

It takes him a bit to notice that the sea is retreating, too busy scanning the deeper waters for a sign of Cthulhu. When he does, his face slackens and his eyes go wide. He startles, trips on the sand when he tries to spin too quickly but before he can all but yell a warning, an enormous wave surges up and crashes down around him, faster and stronger than should be possible.

Just as fast as it came, the wave retreats and Izuku finds himself stunned to realize he’s not even wet. The wave touched everything but himself on the beach, removing what remained of the trash and leaving behind clean, sparkling sand.

Izuku gapes for a second before he becomes horrified. “Not into the ocean! Think of the fishes!”

He feels more than hears Cthulhu’s groan and then the sand beneath his feet shifts, the same tentacles that dragged the All Might sculpture now circle his waist and chuck him into the ocean. Izuku gasps and sputters when his head breaks the water, he removes with a bit of disgust a piece of plastic bag that's clinging to half his face and yells in outrage. “Hey! What was that for?”

In response, the water around him churns and forms a whirlpool, all the trash trapped within the centripetal force with himself floating immobile at the center in defiance of all the natural laws of his world. Izuku has a second to wonder what is going on before Cthulhu’s claws haul him down the whirlpool and the water closes in over his head.

He feels cold rushing through his body and his eyes automatically shut tight. When he was younger, Izuku would drink a lot of cold water in one sitting just so he could feel it slosh around his stomach when he shook his body; the sensation filling his head right now is almost exactly like that. It lasts just a few seconds, Izuku thinks, and then he’s opening his eyes to the view of a pristine beach; clean white sand, clean blue sea. No sight of a speckle of garbage or taint anywhere.

Strong hands grip his shoulders and Izuku finds himself eye to eye with All Might, who is kneeling on the sand and looking him over with frantic desperation. “My boy, are you alright?”

Izuku opens his mouth, closes it, blinks, then actually answers. “Yes? Yes, I’m fine, just- what happened?”

“He dragged you into the sea and-”

All Might doesn’t get to finish because sand is all of a sudden just thrown into his face. The hero sputters and Cthulhu takes advantage of it to answer Izuku’s question.

Izuku is dumbfounded. “You did what”

Then he laughs and laughs, doubling over from the force of his mirth. All Might looks at him despairingly and Izuku, hiccuping, explains: “He sent all the trash through my door to Nyarlathotep’s domain.”

Then what he says catches up with his brain because he screeches, eyes boggling out of their orbits. “Wait, were you always able to take things into myself?”

Training is done early that day, not just because there’s nothing to clean anymore, but because Izuku absolutely has to go home and write about this.

The day he swallows All Might’s hair he’s a nervous wreck. Cthulhu laughs at him and his mother packs breakfast for four (plus an elder god) and then they make their way to the beach. Both Aizawa-san and All Might are already there, waiting for them.

There is no fanfare, no speeches. All Might simply presents a single strand of hair and Izuku inhales deeply, takes it and eats it.

Izuku exhales, and something opens wide inside of him. His door shatters, crumbles, then rebuilds itself anew. It’s no longer one single door, but two, locked together in the middle by a padlock that no longer looks cartoonishly oversized. It looks sturdier, shinier, stronger.

And when Izuku takes it into his hand, it pulses with the same welcoming coolness from Cthulhu’s world. He opens the doors and the darkness swirls as if happy and the cold reaches out enticingly, inviting him within. Izuku knows, without a doubt, that if he so chose, he could step inside.

He laughs at his open doors, both the one inside and the ones waiting for him in the future, and welcomes them all.