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Shouto isn’t stupid.
Sure, according to others he might be dense and a bit cold, (Which, yeah? He has an ice quirk, so obviously) but he’s not stupid.
He knows Midoriya is All Might’s secret love child. The way he reacted when asked during the sports festival? Telling. The way All Might always takes him aside for lunch and their talks? Incriminating. Midoriya’s quirk, and how similar it is to All Might’s?
Damning.
Shouto has it all written down in his notebook, titled UA’s Secret Secrets. He has multiple pages dedicated to this most recent investigation.
Shouto Todoroki will expose the truth, mark his words.
—------------------------------
Shouto sits in homeroom, absent-mindedly drumming his fingers on his desk while absolutely ignoring Aizawa’s lecture about proper hero ethics. It’s almost lunch, which is prime investigation time.
The class lets out a collective sigh as the bell rings, cutting off Aizawa’s rant. Shouto scrambles to shove his supplies into his bag, before-
“I AM HERE, COMING THROUGH THE CLASSROOM DOOR!” All Might’s obnoxiously loud voice reverberates against the walls as the door to 1-A is shoved open. Midoriya bounces over to the hero, his bright yellow bag already packed. He gives a small wave as he and All Might exit the classroom.
Shouto counts to seven in his head - because seven is lucky, yes he’s tested it - before slinging his backpack over his shoulder to follow behind the pair.
He’s done this before, eavesdropping during the different times the two meet, but it’s never really revealed anything substantial. The most he’s gotten was about some quirk named One for All that he tuned out because it was unimportant and unrelated. No use putting it into his notebook- it has nothing to do with his theory, although they do talk about inheritance a lot. That’s in there.
After confirming which room the two were in that day, he walks down the hall to a nearby supply closet. Using the shelves as an impromptu ladder, he jostles the covering to the vent on the ceiling loose, pulling himself inside and replacing the grating.
The vents at UA are much bigger than standard vents - he can sit up in them without hitting his head- and they’re always suspiciously clean. He has another theory that Nezu uses these to get around, as the rat always seems everywhere, but has had no way of confirming it.
Instead, he crawls through the ducts to the room Midoriya and All Might are meeting in. He’s long since memorized the vent system, so it’s only a matter of time before he finds the grate right above his target room.
He quietly pulls out his notebook, pencil, and a bento that Fuyumi made him, and settles down to listen.
“-ne for All is very important. You’re making exceptional progress, young Midoriya!” All Might’s deflated form - that Shouto has appropriately named Small Might- praises.
Shouto represses the urge to bang his head against the steel behind him, settling for a silent sigh and a grimace instead. Again with this One for All stuff! Seriously, what was their deal with it? He has a theory to prove, goddamnit, and this is not helping.
He listens with disinterest for the rest of the hour. It’s more back and forth about that stupid quirk that Shouto elects to erase from his brain. It’s still irrelevant information.
He glances down through the slits of the vent cover to watch as Small Might turns into All Might and exits the room with Midoriya.
He learned about that little part of All Might a month or two ago when he evesdro- uh, theory chased for the first time. He never would have guessed that the scrawny Yagi Toshinori was actually the number one hero, but he’s proved more bizarre theories in the past- his favorite being the fact that Midnight was Yaomomo’s aunt.
That was a fun day, but he digresses.
It seems like the staff already knew about this personality trait of All Mights, so Shouto concluded that there was probably a reason why the student body hadn’t been told. It’s still in his notebook though.
With the room below cleared, Shouto is free to let out an audible sigh. He stews in his misery for a few minutes longer, packing up his supplies and empty bento before making his way back to the supply closet.
Yet another session with nothing learned. Yipee.
—----------------
Shouto’s big break comes in the form of one pink-haired support course student with a penchant for mischief. Mei Hatsume is eccentric, to put it lightly, but after bumping into her once and agreeing to help test out a few of her ‘babies,’ the two became fast friends.
Mei loves listening to his theories almost as much as she loves talking about her inventions, and the two go back and forth during their weekly Tuesday testing sessions. It’s during one of these when Shouto brings up his frustrations.
“I just don’t get it. Something should have slipped by now. I’ve even caught Midoriya calling All Might dad once! I mean, he didn’t know that I was there, but still!” He laments while Mei is attaching some sort of fire-focusing glove to his left hand.
Mei pauses her process to stare up at him with wide eyes. “You never told me about that!”
Shouto blinks, because he could have sworn he had told her at least a few dozen times. It was a big breakthrough in hi- oh. She’s teasing him. He huffs in response as she goes back to her gadget, giggling.
“Awe, don’t be like that! I still don’t understand why that’s not enough, though.”
Shouto sighs. “I need something more substantial than just ‘he called him dad once’. Like DNA or something.”
Mei pauses her attachment for the second time to look back up at him. She has that glint in her eyes that spells both trouble and good results. It’s one of his favorites, for obvious reasons.
She grins. “Why don’t we get the DNA, then?”
Shouto, while more subdued, grins back.
—---------------------------------
Nezu sits in his office, sipping from one of his teacups when his computer dings. He flips through his tabs until he finds where the notification came from, and his eyes gleam when he sees what was happening.
Shouto Todoroki is an interesting student, and Nezu would dare say he’s one of his favorites. On the surface, the boy may seem like your typical higher-class rich kid, but Nezu knows better. Todoroki is a natural-born conspiracy theorist through and through, and that’s what makes him so fascinating.
Within the first week of school, the boy had already discovered Nezu’s ventilation tunnels and explored them thoroughly throughout the next month. Nezu’s pretty sure the boy has them committed to memory, which makes him endlessly happy.
The boy also figured out the identity of Yagi Toshinori within the first two days of class! Granted, it was most likely a happy accident, but Nezu’s glad Todoroki has the sense to keep that to himself. Nezu would hate to have to end their fun over a little hiccup like a secret identity.
On top of all that, he has a notebook he takes with him everywhere and the things Nezu would do to get his hands on it are vast and would definitely be considered villainous. He has a similar want with All Might’s successor - Midoriya’s - notebooks, but this is slightly different.
While Midoriya is analytical and realistic, Todoroki essentially makes something out of nothing, and will not stop at anything to figure out the validity of his outlandish statements. Nezu would love to figure out the thought process behind the almost insane ideas the student comes up with.
And the best part? Todoroki’s theories are almost always correct! He must have a sixth sense for this or something, but that’s what makes it all the more intriguing!
One time, Todoroki witnessed Midnight and Yaoyarozu use their quirks in a similar fashion almost right after another, and got it in his head that they must be related somehow. And lo and behold - through some borderline stalking and asking around - he proved the insane! Truly a feat to be recognized.
Nezu rubs his paws together as he taps into the video within the infirmary room Todoroki and another student - Mei Hatsume - were sneaking into. The two make their way to the computer Recovery Girl uses. Nezu scrambles to turn on the audio as Hatsume digs in her uniform pocket.
“Alrighty, here it is! Baby number three-hundred and forty-one, the ultimate password breaker!” Todoroki is quick to quiet down his excited friend, who just shrugs and plugs in the flash drive. The computer logs in with no trouble, and the two get to work locating the blood samples of the school’s students and staff.
Nezu frowns as he sees Recovery Girl on her way back to the room. If she caches them, then the fun is over, and he can’t have that.
He pulls out his paw-friendly phone and quickly dials her number, muting his computer as it rings, silently hoping the two trouble students find what he already knows.
—----------------------------
“I can’t believe it!” Mei stares with an open mouth at the computer screen in front of them. Shouto pulls out his phone to take a photo, grinning like a maniac. He was going to print this out and put it both in his notebook and his wall. He’d put it on the fridge, but something tells him Endeavor wouldn’t be too happy with that.
The blood sample? Turns out one Yagi Toshinori and one Izuku Midoriya share one common denominator: Hisashi Midoriya.
Hisashi is Toshinori’s brother.
It’s absolutely insane, and Shouto is absolutely here for it. It wasn’t quite what he thought was true, but it was also pretty damn close.
Shouto gives himself an imaginary pat on the back. Another mystery solved.
—-----------
Mei excused herself, still pretty shell-shocked from their discovery, back to the support department. Shouto decides to stick around the infirmary area for a bit, enjoying the feeling of a job well done.
He watches as people go in with some decently serious injuries- most likely the result of after-school training- and come out with barely a scratch. It’s really amazing what Recovery Girl’s quirk can do.
As he watches, he hears a very familiar voice and another slightly less familiar voice enter hearing range.
“-old you not to do that. And what did you do? Not listen, that’s what.”
“Come on, I’m fine! It’s literally just a few scratches, they can heal by themselves. This whole trip is unnecessary and we could be training instead.”
“No. You were reckless. Consider this punishment.” The other person groans in clear complaint as the pair turn the corner.
Shouto’s eyes widen as he sees Aizawa practically dragging a clearly grouchy and scratched-up Shinsou behind him. His teacher barely spares him a glance, and Shinsou just gives him a nod in acknowledgment as he’s pulled into the Infirmary.
Shouto sits there, dumbfounded. What the hell was that? Training? Why was Aizawa scolding Shinsou as if he was his so-
His eyes widen further as he scrambles for his notebook. He flips to a new page, and writes in large print at the top: ‘Theory #34: Shinosu is Aizawa’s secret love child’. He nods to himself. It makes perfect sense! He can’t believe he’s never thought of it before.
He begins to write down all the evidence he can think of, completely tuning out the rest of the world.
Somewhere, on the other side of UA, Nezu cackles to himself.
—-------------------------------
Shouto crawls through the duct system to training room B, the area Aizawa and Shinsou are training in that day.
It’s been two or three days since the infirmary, and Shouto’s been trying his best to tune in to every single training session the two have. He’s filled three more pages in his notebook with many more incriminating interactions and conversations between the two.
Aizawa’s even ruffled Shinsou’s hair! Shouto’s pretty sure that’s a parental thing. He wouldn’t know, what with Endeavor and all, but from what he’s seen online he’s pretty sure it is.
This theory’s almost as good as proven. All Shouto needs is hard evidence, and he’s set. He tried to access the Infirmary files with Mei for a second time the day before, but all the files were wiped. He’s kind of upset about that, but oh well. He proved his Midnight and Yaomomo theory with less, after all.
He rounds one last corner and spies the duct opening on the floor of the ventilation shaft. He sits next to it, looking through the gaps in the vent cover just in time to watch as Shinsou is judo-flipped to the floor by Aizawa.
“Ow- fuck!”
“Watch your language,” Aizawa responds with zero compassion, fixing his student with a glare instead.
“Yeah, yeah, whatever,” Shinsou sits up with a groan. Aizawa extends a hand to pull him up, which he takes gratefully. “Can we take five? I need some water.”
Aizawa sighs but agrees anyway, and the pair walk over to where they left their stuff.
Shouto can tell that they’re talking, but they’ve moved too far away from where he’s situated for him to make anything out. He decides it would be worth it to move to a grate closer to where the two were taking their break, so he silently sets off.
He ends up at a vent opening high on the wall above where Aizawa and Shinsou are resting, tuning into their conversation.
“Oh come one! Another cat would be great.”
“There’s already too many at home. We have like four, Shinsou.”
“And?”
Aizawa pinches the bridge of his nose. “ And it would be ridiculous to get five. Four is too many as is.”
“There’s no such thing as too many cats.”
“Oh yeah? Tell that to the couch.”
Shouto snickers. Who knew Aizawa was so funn-
“What was that?” Shit. Shouto quietly slaps a hand over his mouth and shuffles out of view before Aizawa’s piercing red gaze can spot him.
Shouto’s ears ring as pure silence envelops the room. For a tense few seconds, nothing moves. He’s pretty sure even the air’s gone still.
Out of nowhere, Aizawa’s phone rings, causing Shinsou to jump with a slight yelp. Aizawa sighs, casting one last suspicious glance around the room before he answers his phone.
“Yes? Nezu? What do you want.” Shouto has never been so thankful for the rat in his life. He makes a quiet but hasty retreat as Aizawa’s voice fades into the background.
That was way too close for comfort.
—----------------------------------------
Shouto plans to follow Aizawa and Shinsou to their training session the next day after class, but that’s thrown out the window when he’s asked to stay after school for a talk.
Shouto packs his backpack and waits by Aizawa’s desk as the rest of the class files out. When the last straggler has left, Aizawa speaks.
“Now, I have no idea how the hell you got in the vents, and frankly I don’t really care. What I would like to know, however, is why you are stalking me and my student.”
Oh jeez.
He’s pissed.
Shouto struggles for words.
“I- Well- So, I have this notebook, and- You know what, It’s probably better if I just show you.” He reaches into his backpack, pulls out UA’s Secret Secrets, and places it on the desk.
Aizawa raises an eyebrow as Shouto flips to a random page, beginning an explanation of the theory he lands on.
He’s just gotten past the second page when Aizawa holds up a hand. “Okay, so that’s great and all, but I still don’t see any reason why you’d be following us around.”
“Right, uh,” Shouto flips to the appropriate page, showing off the large print at the top.
Aizawa looks like he’s aged at least three years when he meets Shouto’s eyes again.
“Really?”
Shouto shuffles his feet, slightly ashamed. A minute of silence passes.
“So… Is it true?”
Aizawa runs a hand down his face. “You know what? Ask Shinsou. Just- stop stalking people.” He waves Shouto off, who gratefully grabs his notebook and skedaddles the fuck out of there.
—------------------------------
The next day during lunch Shouto makes it his mission to track down Shinsou. He’s not as familiar with Shinsou’s classmates, but they’re the most likely to know where he is.
So, Shouto calmly walks into classroom 1-C and approaches the closest person to the door.
“Hey, I’m looking for Shinsou. Do you know where he is?” The boy he walks up to looks up in confusion.
“Shinsou? Sorry man, no idea. He kinda just disappears.”
Shouto thanks him for his time before leaving. He knows Shinsou doesn’t eat in the lunchroom, so that leaves somewhere around the school.
Shouto sighs. It’s going to be a long lunch period.
—------------------------------
He finds Shinsou at the top of the East stairwell with around twenty minutes left of lunch. Shinsou narrows his eyes as Shouto walks over.
“...What do you want?”
“Are you Aizawa’s love child?”
Shinsou blinks, stoic facade giving way to confusion. Then he laughs.
It’s… unexpected, to say the least. The purple-haired boy is almost doubled over in laughter, leaving Shouto to stand there awkwardly. A minute passes before Shinsou tries to attempt words.
“I- You-” He gasps for air, wiping - are those tears??- from his eyes as he tries to calm down. He gets his breathing level eventually.
“God, that was the best laugh I’ve had in a while.”
“Was- was it that funny?”
“Yes? You come up to me out of nowhere and ask point blank if I’m someone’s love child. It’s fucking hilarious. Kinda wish I got it on video, to be honest.” Shinsou chuckles.
They sit there.
“So…” Shouto prompts.
“Usually I’d say it’s none of your business, but that was funny, so whatever. Aizawa and his husband adopted me a month or so ago. So, technically no, but legally kinda.”
Shouto’s eyes widen. “Aizawa’s adopted someone?”
Shinsou looks confused. “...Yes? That’s what I just said?”
Shouto’s eyes almost sparkle. “Aizawa has a husband?? ”
“Whoops….”
—------------------------------
The next day, Shouto’s back in the vents, this time gunning for a very specific opening.
The teacher's lounge.
Class is in session, so there really shouldn’t be anyone in the room at the moment. He finds the cover he’s looking for, and, thankfully, it’s empty.
Shouto wastes no time removing the grate and dropping down into the room, walking to a specific desk. He’s already gone through Aizawa’s desk in class, which yielded no results, unfortunately. He’s not looking for much; just a picture or a note or something.
He rummages through the desk drawers, scanning over everything. He’s just gotten to the second row when he hears footsteps get closer to the room, along with a few voices.
Well.
Shit.
Shouto curls under the desk, closing the drawer he had opened just as two new people enter the room.
“I’m telling you, Hizashi, there’s something in the damn vents! I’ll be sitting there, minding my own business, and then I hear this quiet scuffling from the walls!” Midnight says.
“You sure you’re not just going senile? Thirty is pretty old…” Present Mic trails off.
“Oh shut up! We’re literally like the same age!”
“Whatever helps you sleep at night.”
Midnight lets out a displeased hum as a pair of footsteps crosses the room. Shouto hears a few papers rustle before the footsteps go back to where they came from.
“There, conference briefing. Can’t believe I forgot it.” Mic says triumphantly.
“I can’t believe I went with you to get it.”
“Hey, anything to get out of the rat’s meetings.” The two chuckle before they exit the room, closing the door behind them.
Shouto counts to seven. Just in case.
When the cost is clear, he hesitantly gets out from under the desk to resume his snooping, slightly jittery from all the adrenaline of almost getting caught.
He eventually comes across a photo of Aizawa sitting on a couch, swarmed by a group of four cats. Running low on time - the bathroom excuse can only be used for so long - Shouto snaps a picture of it with his phone before returning the frame to the bottom of the drawer.
That’d have to do, for now, he supposes. He climbs back into the vent, carefully replacing the cover before heading off back in the direction of the classroom.
—-----------------------
After school, Shouto finds a quiet corner to pull out his phone and study the photo he found.
Now that he has more time, he notices some details he didn’t see before, like the fact that Aizawa has a chain with a wedding ring around his neck, and the fact that there’s a diploma on the wall in the background, with the name ‘Yamada Hizashi’ written on it.
And, well, isn’t it funny that that’s Present Mic’s name?
Shouto’s practically vibrating with excitement. He hastily writes everything down in his book, leaving some space to print out and glue in the photo so he can circle the important parts with red pen.
Now, the only thing left is to find Present Mic’s wedding ring. That’ll be solid enough evidence to consider this theory proved.
And Shouto has just the plan for that.
—----------------------------
“Hey, Midorya, do you think you could ask All Might if we can fight against some of the teachers sometime?”
Midoriya tilts his head. “Sure…? But, why?”
“Well, he’ll probably listen to you more than he’d listen to me. And I want to know if any of us could win against a pro.”
Midoriya nods. “Yeah, I can do that. Who were you thinking?”
“Teachers who would be the worst matchups for us. Like Present Mic for Jirou and Shouji, or something.”
“Alright. I’ll see what I can do!” Shouto smiles.
“Thanks, Midoriya.”
—--------------------------------
The next day during heroics, Shouto is happy to see Present Mic, Cementoss, Midnight, and Ectoplasm standing next to All Might and Aizawa.
The class splits off into groups of five. Shouto is supposed to go against Midnight with Sero, Kaminari, Midoriya, and Tokoyami. Their group is going last, so Shouto has time before he sneaks off.
At the tail end of Cementoss’ fight against his classmates, Shouto walks up to All Might and asks if he can use the bathroom. He pointedly ignores the suspicious glance Aizawa gives him as he walks off in the direction of the main building.
Once out of sight, Shouto finds his way into the vent system. He’s not completely sure where the teachers leave their stuff, but he’s betting it’s near the staff entrances at the back of the school.
Eventually, he comes across what looks like a locker room. He sees the names on the lockers and immediately knows he’s where he needs to be.
He climbs into the room and walks over to Mic’s locker. It has a padlock, but Shouto has a workaround for that. He puts his right hand up to the lock and sends his ice into it in place of a key. It opens with no resistance.
Shouto’s ecstatic to see exactly what he was looking for.
Hanging on the back hook of the locker is a chain with a wedding ring on it. The exact same kind as Aizawa’s. Shouto smiles and pulls out his phone for a photo.
He’s about to put his phone back when white cloth comes out of nowhere and traps his arms to his sides.
Uh oh.
Aizawa steps into the room from outside, rubbing his temple with one hand.
“Todoroki, what the hell are you doing.”
Shouto smiles sheepishly. “Uh… giving my congratulations to you and Mic…?”
Aizawa stares at him. “I have no idea what you’re talking about.”
“Your matching wedding rings and Mic’s diploma in your house say otherwise.”
Aizawa’s stare turns into a glare. “What did I tell you about stalking people?”
“Not to do it. And I didn’t, technically…”
“I’m not paid enough for this…” Aizawa grumbles. He says nothing else as he turns around and leaves the room, dragging Shouto behind him with his capture scarf.
Shouto doesn’t say anything. He probably deserves wherever they’re going.
—---------------------------------
They end up in front of the principal’s office. Shouto silently hopes he’s not expelled.
Aizawa opens the door and pulls Shouto inside, sitting him down on a couch in front of Nezu.
The rat smiles, “Thank you Aizawa!” Aizawa nods and leaves the room.
Nezu turns his beady little eyes to Shouto. “Now, Todoroki, contrary to Aizawa’s beliefs, I am very much aware of your activities. Frankly, I think they’re wonderful!”
Shouto blinks. That was… not what he was expecting.
“It’s been a joy to watch you fill out that notebook of yours, and you obviously have a knack for this sort of thing. So, I have a proposal for you!”
Shouto nods, signaling for him to continue.
“I could give you a school-wide pass. This would allow you to go basically anywhere, within reason, and not get in trouble for it! All I wish for, in exchange, is to be able to read your notebook every once in a while.”
“...Is that really all?”
Nezu smiles. “Well, I may ask you to figure out a few things for me. While I love to joke about my omnipotence, I’m not actually a god. There are a few things I can’t find out for myself, due to my status, and that’s where you’d come in! Does that sound reasonable?”
Shouto tilts his head. It… doesn’t sound bad, actually. This way he wouldn’t have to sneak around as much. What Nezu seems to be suggesting isn’t as much proving theories as it is investigating, but…
Well, Shouto doesn’t think he’d mind. It sounds fun, actually.
“Alright. I’m assuming you want to see my notebook right now?”
Nezu’s eyes practically gleam.
Shouto wonders what exactly he just got himself into.
Fin.