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Chapter Text

Mitsuha's chest felt strange. It was sore and for the life of her she couldn't figure out why. As she walked down the path to school with her friends Sayaka and Tessie, she contemplated whether or not she should tell them. Sure, they were friends, but not even friends would tell each other that their breasts were aching.

To add onto that, Tessie was still a guy, so it might not be the most appropriate course of action.

But it was killing her.

She grabbed Sayaka by the arm and said to Tessie, "hey, Tessie, I need to talk with Saya about some girl things, why don't you go on without us for a bit?"

Tessie's eyes went back and forth between the two girls. It was unusual for Mitsuha to request a private audience with Saya, but since they were girls, it probably had something to do with their girl biology or whatever it was.

Sayaka, on the other hand, seemed more than delighted to shoo Tessie away from the two. Taking note of her hostile remark, he blew her a raspberry before heading along the path with his bike.

"Well," Sayaka said, "now that the weirdos are gone, what did you want to talk abou-geh?!"

Mitsuha grabbed Sayaka by both of her shoulders, and from what Sayaka could tell, she was crying. This wasn't the kind of "sad revelation" type of crying. This was more like the "ate a raw jalapeno and just realized how spicy it was" type of crying. Beads of tears were forming in the corners of Mitsuha's eyes, but they haven't exactly streamed down her face. She was definitely holding something in.

"What's wrong, Mitsuha? You need to use the bathroom that badly?"

Mitsuha shook her head in a somberly slow fashion. She leaned in and whispered to Sayaka, as if there were invisible people that would pick up on her words if she said them at a normal volume. "My chest."

For a second, Sayaka had no idea what was going on. What about Mitsuha's chest? Were they-

She pushed Mitsuha back and leaned forward, her face mere inches away from Mitsuha's bust. She squinted at it, and for a second, she thought Mitsuha meant she had grown. Sayaka had never felt more betrayed than she did at that moment. It was bad enough that she herself was about as flat as a washboard, but now Mitsuha was growing larger?

She grabbed Mitsuha's sides and shook her violently. "Quick, Mitsuha! What are you eating at home?!"

Her voice rising and dropping in pitch as her friend interrogates her, she replies, "I'm jUSt EAtinG WhaTEVer we HAVe aT HOme...!" As her brain felt like it was about to fly out of her skull, she couldn't help but wonder how this conversation managed to derail itself before it even got on track. Was Sayaka really this self-conscious about her chest?

"THEN WHY ARE THEY SO BIG?!!" Sayaka screams as she falls to her knees in defeat. Releasing Mitsuha, who was now faced with the task of regaining her balance, she continued to bawl her eyes out right there on the dirt path, drawing the eyes from a few confused residents.

By this point, Mitsuha no longer felt pain in her chest. Now it was a completely different feeling. As she continued to watch Sayaka break down in front of her, her face drew into a scowl. This, this is what she deals with every day. By now, that pain had been replaced with pity.

Mitsuha stared at Sayaka.

You poor thing.

Chapter Text

September 15, 2013

My name is Yotsuha Miyamizu. I am writing to inform you, future me, that your sister is gone. She has been replaced by a demon, a ghost, I don't really know, but it's creepy still. If you are reading this ten years from now, then listen to my advi-

"Whatcha writing there?" Yotsuha heard a voice over her shoulder. Frantically, she covered the notebook she had been writing her memoirs in.

"It's nothing!" Yotsuha yelled.

"Nothing, huh," Mitsuha expertly grabbed the notebook from under Yotsuha's arms. "Doesn't look like nothing to me." As she waved the notebook in the air, she couldn't help but feel like teasing her sister a bit. "You got a boy you like?"

Yotsuha replied with an ungodly war cry as she tackled her sister to the ground, wresting the book from Mitsuha's grasp before bolting out of the room like her life depended on it.

Mitsuha just lied on the floor, still in shock. What did Yotsuha have in there that made her so against her seeing it, and since when was she so strong?!

Every morning was an internal battle for me, Yotsuha Miyamizu. I know that whenever I'm going to slide the door to Mitsuha's room open, I'll be confronted with a horror the likes of which had never been experienced in the history of mankind—or at least the bits I learned in school. Ohh, my hands are shaking just at the thought of it...

But I have to! As a proud Miyamizu, I must be strong! I am a shrine priestess in training, and today will be my first fight with a demon.

I turn on my heels to find something to use as a shield. Or anything I can throw at Mitsuha.

Doesn't hurt to be too prepared, right?

I can't believe I'm going to do this.

As I watch my sister walking to school, in a ponytail for some reason instead of the braids that she said our mom taught her, it confirmed my suspicions. Today, this was evil-spirit-monster-fox-demon-ghost-Mitsuha! And in order to know how to defeat it, I have to know how it behaves.

So I'm going to trail this monster to school and watch it all day. I won't let it out of my sight for a second!

Then I look around and realize that she's already out of my field of view.

A sly one, this is. A sly one indeed.

I come home exhausted. I throw my bag at the entrance to the house, I'll come back for it later. "I'm home!" I call tiredly, dragging my feet across the wooden flooring before collapsing onto my stomach. Today was horrible. I wasn't actually allowed into the building since I wasn't a student there, but during lunch, I noticed something interesting. Sis was getting along awfully well with Katsuhiko Teshigawara. In fact, I'd say she's getting along too well with him. But why? Form the look of pure disgust on Sayaka's face, I can only come to one conclusion.

My sister and that boy are dating!

Argh, that riles me up! So that's why she's acting differently! My sister's trying to change herself so Teshigawara will like her more! Unforgivable, I'll have to find a way to make him pay.

Just then, the house phone rings. I pick it up, since grandma's probably busy. "Hello?"

"Hey, Yotsuha, could you help your big sister out with something? I need you to get my..."

Grandma walks into the room after a while. "Who was that, Yotsuha?"

"Big sis. She wants me to bring her sweatpants for some odd reason. Anyways, I'll be right back!" I rush out carrying a plastic bag with Mitsuha's pants in here. What could she possibly need from a pair of pants? Suddenly a terrifying realization comes to my mind.

Could it be that sweatpants are Teshigawara's fetish?!! That horrible scumbag! What doesn't he like about my sister's legs as is?! They're beautiful; why cover them up? Is he trying to say my sister's legs aren't worth peeking at?!

Come to think of it, why am I thinking about my sister's legs?

Arghhh, I'm getting so many mixed messages in my head!!!

I drop off the pants at where she said to meet. Mitsuha grabs them and pats my head. "Thank you, sweetie," she said.

"Sweetie...?" I repeat, and I feel the distinct taste of vomit building up in my mouth. This has to be another one of Teshigawara's antics. Looking past my sister, it seems like they were building something. There are chunks of log everywhere, and some kind of table in the middle made out of those logs. Are they trying to build a rest stop or something?

Well, whatever, Mitsuha did promise to buy me ice cream on the way home for helping her, so I guess I'll just wait around. So I sit on the grass and observe the two. As I watch them talk to each other with enthusiasm, I'm starting to understand what's going on.

My sister...is brainwashed.

No, I will not stand for this! I will not surrender my sister to this man! If you want Mitsuha, you'll have to pry her from my cold, dead hands!

"KATSUHIKO TESHIGAWARA!" I yell, startling both him and my sister, who immediately drop what they're doing and turn to face me with surprise. I remain strong. "I demand you break up with my sister immediately!" Both of them stare at me, then look at each other, and back to me before simultaneously asking "huh?"

Don't give me that "huh" stuff! I know you're the reason my sister is doing this weird stuff! Every morning she touched her boobs because you call them small! Every day she ties her hair into a ponytail instead of her usual hair because you like it better that way! Even now, you're making her wear sweatpants because you don't like her pants! You're cruel!" I turn to face Mitsuha. "Big sister! Remove your pants at once!"

. . .

I feel like an idiot. Teshigawara starts laughing as my sister pulls me to the side to explain to me that I've got the completely wrong idea.

"You mean you're not covering your legs because he called them ugly?"

"No, Tessie said that I should wear it so I can have more freedom of movement than just wearing this skirt."

"And your hair?"

My sister looked around nervously, "Uh, I just...sometimes I feel like trying something new, you know?"

I pry deeper. "And your boobs?"

"...Just go home, Yotsuha." Clearly she did not want to talk about that last one. But I have to make sure I'm properly paid for my efforts.

"Do I still get ice cream?"

"...I'll think about it."

"You really are a demon!"

Chapter Text

Mitsuha felt an unusual attraction to the scenery beyond her classroom. The clouds overhead formed a peculiar spiral-like shape. In the center of that spiral was a single ray of light that shone directly onto the outside soccer field. No, wait, football? Do we even call it soccer in Japan?

Who am I even asking? Mitsuha thought to herself.

Despite that, she couldn’t help but feel unusually drawn to the unnatural formation in the sky. She’s heard of certain clouds having certain pattern principles before, but nothing as intricate as a near-perfect spiral in the sky.

“Miyamizu? Miyamizu?” Ms. Yukino said. Mitsuha jumped from her seat, nearly tripping over herself. Good thing she didn’t though, since she’s the main character, and non-shounen main characters aren’t supposed to be subject to unnecessary violence.

As class was reaching its last few minutes before lunch, Mitsuha noticed something falling from the sky. Something small and black, almost like a book of some sort. As her eyes traced its path through the sky, she felt strangely drawn to it. Part of it may have just been that the book was being highlighted by the single ray of light all the way down. That’s some heavy symbolism going on, and Mitsuha knew that that meant the book was going to have significant effects on the plot. Her mind snapped back to attention as she watched the book fall to the ground unmoving. There it was, in the middle of the field as if someone had abandoned it like a [CENSORED].

Mitsuha knew that this meant only one thing. It was up to her to retrieve that notebook.

Once class ended, Mitsuha bolted out of the room, barely even stopping to tell Sayaka that she’d be waiting at the same desk and chairs out by the tree next to the field. She rushed over to the book and without hesitation, snatched it up from the ground before anyone else could question her. She immediately plopped down one of the old chairs and flipped through the book. It was calling to her. It was reaching out to her.

Whatever was in this book, it had something important to her.

She flipped back to the front cover and found a strange list of what appeared to be rules written across it in very messy handwriting. And English.

Mitsuha thanked the stars that this story was being written in English. She read the first ruling out loud: “The human whose name is written in this note shall die.”

“No way, really?!” Tessie exclaimed. Mitsuha’s hair stood on ends as she jumped back, almost falling out of her chair. Behind her for who knows how long were Sayaka and Tessie, both of them eyeing Mitsuha with curiosity brimming in their eyes.

Mitsuha immediately stuffed the notebook into her bag.

“Woah, Mitsuha!” Tessie exclaimed with excitement, “I didn’t know you were into that stuff too!”

Sayaka responded with a sharp blow to the back of Tessie’s head. His yelp was strong enough to crash the very heavens above.

Mitsuha skipped to herself going back home. She charged through the entrance and startled her sister Yotsuha, who was putting on her shoes to throw out the trash.

“S-sis?! What’s the rush for?”

“Sorry, Yotsuha! I need to be alone for now!” Mitsuha ran up the steps like a possessed demon monkey, and Yotsuha sighed to herself.

“I’ll never understand adults.”

Mitsuha locked herself in her room. She slapped the book onto the table and reread the rules written on the inside cover.

“The human whose name is written in this note...shall die?” Her eyes went over the rules over and over and over again, but she still couldn’t wrap her head around it.

After a while longer, Mitsuha gave up, lying on her futon in defeat. “Whatever,” she sighed, “it’s probably just some elaborate prank.”

…

So how did it fall from the sky?

“Mitsuha, you’re not coming to school today?”

“No...I don’t feel so good today.”

“O-oh, I see. I’ll come by later today to drop off assignments.”

“Mhm, thanks, Saya. See you.”

Mitsuha set her phone down and couldn’t stop herself from grinning like a maniac. After spending an off-screen night testing the notebook’s powers, she was elated to discover that the notebook was in fact true.

Her grin slowly progressed into a wide smile, and then it turned into hysterical laughter.

Yotsuha paused on the staircase. She was supposed to come upstairs to get Mitsuha down for lunch, but…

“Oh?” Hitoha asked, “is Mitsuha not joining us?”

Yotsuha shook her head. “I think she’s lost it.”

Mitsuha continued to giggle alone in her room with glee. She’d nearly fallen out of her chair at least three times, but there was no helping it.

The notebook was no fake. The names of all the people she wrote in it, they never showed up again. The kids who tried to bully her in school, her dad's friend's subordinate's associates, who she'd never even met before, dead. Everyone single person she wrote down was dead.

She leaned back once more in her chair until the sound of cracking thunder shocked her, causing her to actually fall.

Mitsuha turned around and screamed. Standing before her in her room was a boy, one that looked no older than her, but his face was expressionless. He simply stood in the corner of her room, watching her with a pair of deep blue eyes.

Yotsuha burst into the room. “Sis, what’s with the loud ruckus?!”

Mitsuha pointed at the boy, “th-th-there’s a boy s-standing there!”

Yotsuha looked at where her sister was pointing, then back at her sister. “What are you talking about?” She asked, “I don’t see anything. I swear you really have lost it.” Yotsuha then left, sliding the door shut behind her.

Once Yotsuha left, Mitsuha managed to regain her composure. “Who...who are you?” She asked the boy.

The boy simply smiled. “I’m the one you stole that notebook from. My name is Taki.”

Mitsuha gasped at his name. Then she threw the book at him. “No way, you’re supposed to be the shinigami?”

Taki held his arms up in defense. “Look, it wasn’t my idea! The director wanted a- hey, where are you going?!”

“I’m done with this! I was hoping you would’ve been L or something so we could have a cool thing going on, but I guess not!” Before leaving, Mitsuha grabbed a packet from her desk and threw it offstage. “Keep your crappy script!”

Mitsuha stormed off the set, followed by Taki, who tried to reason with her to no avail. The entire set stood awkwardly, unsure of what to do before Yotsuha popped her head from behind the door.

“Are we retaking that?”

Chapter Text

So Teshigawara isn’t the cause of my sister’s weird antics. That still doesn’t excuse her being weird! I’ll get to the bottom of this, for Mitsuha’s sake!

On another morning, I peek into my sister’s room. She’s tying her hair up in a ponytail. Fat giveaway, she’s not feeling normal.

By now I’m convinced my sister is possessed. Every day she acts weird is a day she ties her hair into a ponytail. Maybe...maybe the ponytail is what causes her to turn into a weirdo!

“Oh!” Mitsuha exclaims, “I forgot I’m supposed to meet up with my friends today!” She gets up and immediately heads out.

Suspicious. Meeting with friends on a weekend? Fat chance, there’s something fishy going on, and I’m going to put a stop to it.

Mitsuha’s going to...school? No, not school. This was the place she went to last time with Teshigawara. My poor sister, falling into the trap of some inner demon. Luckily for her, I happen to be an amazing sister, and I know just what to do.

I follow my sister all the way down the road until she meets Teshigawara and Sayaka under the shade of an umbrella atop their little makeshift wood patio-couch-thing. Mitsuha looks like she’s having fun, but that smile can’t fool me. That’s the smile of a soul trapped, begging for help.

It looks like they don’t notice me. I crawl among the grass, making ever so slight movements, burying my face into the ground when their eyes begin to turn towards me. It’s a good thing I brought a green hoodie.

...How long has it been? They’ve done nothing but chat all day. What do they even have to chat about?

None of them have moved from that spot. They’re all just sitting together talking about stuff. Mostly my sister and Teshigawara, Sayaka looks just about as confused as I am. Maybe she’s also a victim in all this.

Geez, my sister and Teshigawara are really getting into it. Mitsuha stood up on several occasions so far. Did she ever talk this much? Especially about architecture, since when was my sister into that baloney?

Ugh...hurry up and do something suspicious…

I’m getting bored...and a little drowsy...you know, the grass isn’t all that bad, pleasantly soft...zzzzzzzzzzz

“Yotsuha?”

...

“Yotsuha!”

“Bwah!” I wake up with a start. Did I...did I fall asleep on the grass? Huh, I ended up sleeping a lot longer than I thought I would.

That’s strange though, did someone turn off the sun?

I look up and see my sister staring down at me with a disappointed look.

…

…

…

My cover’s been blown!

I immediately jump to my feet. I point a finger accusingly at my sister. “Sis! What’s wrong with your hair?!”

Mitsuha places a hand over her ponytail in a defensive matter. “What?” She asks, “what’s wrong with it?”

I lunge at her, jumping onto her torso, wrapping my legs around her waist the same way they did on TV. This should be enough to subdue the demon. “I won’t let this demon take you!”

I tug at the ponytail. My sister yells in pain and runs around flailing. Trying to shake me off, eh?

Not going to happen!

I lean backwards, forcing both of us onto the ground. I then maneuver myself to sit onto my sister’s back. I grab the band holding her ponytail into place.

“This ends here! Give me back my sister you demon!” I pull the band off, releasing my sister’s hair, and with it, her true spirit.

No need to thank me, I’m just-

My sister pushes herself up. Such strength! I lose my balance and fall off her back. Who would’ve thought that being 8 years older than me would give her such a huge advantage?

Mitsuha looks at me with alien eyes. Her face contorts into one of unbelievable anger.

I would probably laugh at it if I wasn’t so terrified.

Tessie and Sayaka watch as Mitsuha grabs Yotsuha by her shoulders and begins shaking her back and forth violently.

“...You think we should step in and help them?” Sayaka asks.

Tessie sits back in one of the wooden chairs, leaning back to watch the episode before him. “I’m fine where I am, thanks.”

Sayaka groans as she covers her face in embarrassment. Mitsuha is now tugging at Yotsuha’s twintails.

“Ow, ow, ow! Stop it, sis!” Yotsuha yelps.

“Let’s see how you like it, kid!” Mitsuha bellows.

...Yeah, they were siblings, all right.

Alright, so my plan to defeat the demon inside of my sister failed. So what? Aside from the fact that I woke up with grass sticking to half my face, I learned a lot about her. For instance, she’s a violent brute.

Oh, who am I kidding, my sister would never do that!

I read somewhere that demons only enter the body right before you wake up.

The next day, I tiptoe into my sister’s room as she’s sleeping. I carry a pillow with me, a weapon of sorts, to ward off the demons before they can possess her. I make my way carefully over to my sister’s side. And then…

...I whack her repeatedly with the pillow.

“Take that, you monsters!” I cry, smothering my sister in soft padded aggression.

My sister wakes up choking. “Y-Yotsuha! What in the world do you think you’re-”

I ignore my sister. All her pleas to stop will be nothing compared to the gratitude she’ll feel after I save her from this onslaught of demons.

I continue batting her for a couple more seconds. At last, my arms wear out, and I wipe the sweat off my forehead. Fighting monsters is quite the workout!

I look at my sister now, who someone manages to appear even more demonic than before.

“...Yotsuha.” She says sternly.

“Y-yeah...?”

“What do you think you’re doing?”

I drop the pillow and my legs begin to wobble. I turn to run away, but a strong hand grips my wrist. There was no escape.

Mitsuha stood up ominously over me, glaring at me with murderous intent.

“I hope you’re prepared to face the consequences,” she says in a deep tone.

My voice turns into little more than a whimper. “I...wait...let me-...”

My sister, without releasing her grip on my arm, reaches down to grab the pillow, and turns to me with an evil grin.

I close my eyes, and I take a deep breath as I make peace with my life.