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Now Eijirou has seen a lot of things in his sixteen years of life.
He'd seen Denki practically inhale an entire table of food at the UA Gala last December.
He'd watched as Midoriya went on a murderous rampage, brutally tearing apart the dorms until he found out who put a stain on his Limited Edition Young Age All Might 'Mighty Boys Need Mighty Sleep' Matching Bed Set.
It was Iida. The poor child had never been more terrified in his life. He was flinching for weeks afterwards, grovelling at Midoriya's feet everytime he walked past.
Eijirou could still hear the screams, the cries for help as Midoriya's victim was dragged across the boundary line of his room and the door was shut behind him. There was nothing they could do then. Midoriya's room was a lawless land of chaos and Eijirou was lucky enough to have avoided it for this long.
But this? Standing in the supermarket, buying a box of red hair dye and watching as Aizawa-Sensei — who was obviously trying to be inconspicuous, and doing a terrible job as his clothes screamed "PAY ATTENTION TO ME!" rather than "Ignore me. I am but a ghost in the room, a trick of the light" — stared intently at the product in his hand.
The product which was, Eijirou stepped closer to see better, a box of hair dye?
But what would Aizawa-Sensei need hair dye for? Unless one of his friends — Aizawa-Sensei had a life outside of teaching and being a pro hero and Eijirou was more than willing to die on that rock, fuck you Sero — needed it? Or maybe! Maybe he had his friends over, and they got drunk and played strip poker which was why he looked like a child had attempted to dress him in the dark — seriously, he was wearing a neon yellow hoodie with bright red tracksuit bottoms and brown hiking shoes. And then, of course, they had to have played drunk truth or dare with his friends, which is why he was here at the shops, because he was going to dye his hair bright yellow.
Eijirou squinted at the man, his mind telling him that story was just a little bit far-fetched. Aizawa-Sensei was more of a "I've just had a mental breakdown and/or existential crisis, and instead of dealing with my emotions in a healthy way I'm gonna go dye my hair bright blue." kind of guy than a "My friends dared me to" dude.
But back to the point.
Aizawa-Sensei was buying hair dye, and Eijirou had no idea why.
He smiled — only a little evilly — wondering if this is how Monoma felt everytime he antagonised his class, before moving closer.
Now Eijirou had never really excelled at being stealthy or discrete, so it wasn't really all that surprising when half-way through his slow pursuit Aizawa-Sensei turned to face him.
What was surprising, however, was the way his teacher snapped his head away so fast that Eijirou was worried he might get whiplash.
"Aizawa-Sensei?" He called out tentatively, hoping that he hadn't broken his neck in the turn.
"Who–" the man cleared his throat before continuing, his speech coming out lower than before. "Who?"
Eijriou walked closer to his teacher, head tilted in confusion. Who? Was Aizawa-Sensei hit by an amnesia quirk? Now that he thinks about it properly, it makes a lot of sense. Eijirou knows for a fact that his teacher would never be caught dead in the clothes he was wearing. It was either black or dark grey. That's all he wore. And he would never buy hair dye either, so he must have been hit by a quirk!
Though whether it was an amnesia quirk or a body-swap quirk, Eijirou couldn't be sure.
Midoriya would probably know, but as much of a fanboy as Eijriou is, he didn't know his teacher's little quirks and mannerisms.
He remembered how Midoriya had attacked Cementoss that one time when the man had smiled, because "Cementoss doesn't smile in public. You've been caught Toga, reveal yourself."
Yeah, he got a detention for that. And he had to write an apology to Cementoss too. The poor guy was crushed for weeks after.
But Eijirou didn't know if there was someone using Aizawa-Sensei's body, or if he was being impersonated, or if he had amnesia.
"Are you okay Aizawa-Sensei?" He said slowly.
"Of course I am– I mean– Who's this Aizawa fellow you speak of?"
"Shit, this is worse than I thought," He muttered to himself. "Okay, what's the last thing you remember before waking up in this body?"
"Waking up in this– Kirishima! I haven't been hit by a quirk!" Aizawa-Sensei(?) Turned to face him now, though Eijirou's view of the man's face was obstructed by his hand which rubbed relentlessly at the spot between his eyebrows.
"Oh yeah?" Eijirou tried to sound tough but he was mentally scrambling for something to ask the man to make sure that he was actually Aizawa, and that he wasn't under the effects of a quirk — because seriously, who wears bright yellow hoodies? Who wears bright yellow at all?
"Well then tell me something only Aizawa-Sensei would know."
The man made no outward reaction, the hand on his face only stilling slightly.
"You failed your last mid-term, I had to get Cementoss to reconstruct the dorms 2 weeks ago because you woke up in the middle of the night and tore the dorms apart because you thought you lost your favourite Crimson Riot hoodie."
Eijirou shrunk back at that, mortification still flooding his body at his past actions.
"Okay, you can stop now–"
"You have a crush on Monoma which, ew, why would you want a loud blonde in your life?"
"Okay that's enough–" Eijirou blushed, face almost as red as his hair.
"You once ate Bakugou's lunch which he'd left in the fridge, and shoved the blame onto Kaminari because, and I quote, 'I'm too manly to die' which just isn't how it works." Aizawa was using his free hand to list things as he went, opening his fingers quickly as he counted everything he said.
"And then there was that time you thought you had a crush on Sero and instead of dealing with it like a normal person, you called me and ranted at me for 3 hours about your worries which then devolved into all the things you liked about Sero speech which–"
"THAT'S ENOUGH"
Eijirou shot forward, shoving his hand at his teacher's mouth, uncaring of how loud and rude he was being. The entire shop probably heard him, but he didn't care. He just needed Aizawa-Sensei to shut up before he was forced to relive all of these embarrassing things he'd been repressing.
His teacher glared at him from behind his hands, and the only thing Eijirou could think of doing was smiling at him, though it felt more like a grimace than a proper smile.
The man slowly brought his hands up to his face and wrapped them around Eijirou's wrists before guiding them back to his sides.
His hood shifted slightly as he moved the hands away, sliding back a little on his head until his hairline was only just visible.
Eijirou was looking at the floor, so he didn't notice, but when he brought his head up, he gasped as it caught his eye.
He rushed forward again, yanking Aizawa's hood back until his whole head was revealed.
"YOU HAVE RED HAIR?!" Eijirou shouted, uncaring of the volume of his voice and the proximity of his mouth to his teacher's ear.
Aizawa moved back abruptly, bringing the hood back over his head and pulling the draw strings closed so fast that they vibrated for a few moments after.
But Eijirou knew what he saw, and the hood wasn't going to erase the picture of Aizawa-Sensei's bright red roots which had practically been burned into his mind.
"No I don't."
"Yes you do!" Eijirou moved after his teacher who had decided to start walking away. Aizawa never walked away from anything! He stood up to the Noumu at the USJ and yet here he was, running away from Eijirou as fast as he could without making it look like he was shoplifting.
"You're seeing things Kirishima, maybe you need glasses."
"I do not need glasses!" Eijirou was a little offended that Aizawa-Sensei had even suggested such a thing. "I know what I saw!"
"No you don't" The man slipped around the corner of the aisle and made his way towards the cash desk.
Eijirou wouldn't let him get away so easily though.
Which is how he ended up locked in a storage room beside the pet food aisle.
The only thing that stood between the locked door and his teacher was Eijirou, and he probably should have thought this through before acting.
But he hadn't.
And sure, it was incredibly rude to do this to anyone — let alone his teacher — but it was Aizawa-Sensei, and he was used to the bullshit their class got into on the daily. Eijirou would be fine!
"Move Kirishima."
"No." He shook his head from side to side vigorously, as if that would instill any sense of obedience in his teacher, who could easily overpower Eijirou if he wanted to.
"Kirishima." His teacher's tone was bored, but Eijirou could hear small hints of pleading in his tone, something he never thought he'd hear from the apathetic man that taught them.
The most emotion he'd ever shown was a small uptick of his lips when Mineta was finally expelled.
"No." He repeated, "I know what I saw and– and I'm not letting you leave until you explain."
Aizawa-Sensei cocked an eyebrow at that. "Really" He said, "Is that supposed to be a threat?"
Eijirou fumbled for words for a moment, fiddling with the drawstrings of his own hoodie, the hood pulled low over his forehead.
"You can't leave until I say or… Or I'll tell everyone about this! About your hair!" He smiled, knowing his teacher wouldn't want this to get out.
"Is that it?" Aizawa asked, almost bored. "No one's going to believe you, so it doesn't matter anyways."
"I'll– I'll tell everyone that you actually like our class!"
Aizawa's eyes went wide at that, and a look of genuine fear passed over his face.
"NO!" The man shouted, flinching at his own volume. "No. I'll… I'll tell you."
Eijirou's jaw just about hit the floor. There's no way it was that easy, right? But here Aizawa-Sensei was, about to tell him about why his hair was red. And all because he threatened to tell everyone that he liked their class?
He found himself a little sad at the implications of that. Either Aizawa-Sensei secretly liked their class, or he hated them such that he couldn't stand to have anyone spread such lies.
"It's because of my quirk."
Eijirou was shaken from his musings at the beginning of Aizawa-Sensei's explanation. He pulled two boxes across the floor, sitting on one and patting the other expectantly.
"Fine." The man sighed, sitting down beside him before continuing his explanation.
What followed was a very long and detailed explanation of Aizawa-Sensei's quirk and how it worked. And Eijirou tried to listen, really, he did. But there's only so much talk about quirks he could stand.
Basically, it all boiled down to "The more I use my quirk, the more red hair grows." Which Eijirou thought he should tell Midoriya, knowing the other not would be fascinated by the information.
And Monoma, if he wanted to avoid the other boy looking like a box of McDonald's fries.
…
On second thought, maybe he wouldn't. Photo evidence of that could serve as useful blackmail should he ever need it.
"Are you happy now?" Aizawa bit out between gritted teeth.
Eijirou went to say yes, to confirm that Aizawa didn't have to say anything else
"Oh for fuck's sake."
"It's just a small question, I swear!" Eijriou was practically begging the man to answer him.
Aizawa was listening though, as he unlocked the door and walked back out into the shop, boxes of hair dye in hand.
And Eijirou… Well, he was a little desperate.
He scrambled up off of the floor and ran back into the shop, skidding around aisles until he stopped in front of his teacher.
"It's just," He gasped for a breath of air, of the oxygen his lungs desperately needed after the surprise sprint he'd just performed, "one question."
Aizawa's eye began to twitch at his antics.
"You won't let me leave until you know, will you?"
"Nope!" He breathed, slowly regaining his breath.
It was quiet for a minute as he breathed, Aizawa watching him with an expression that was equal parts wary and annoyed as it was bored and apathetic.
He was almost impressed at his teacher's ability to have such confusing facial expressions.
"So…" Eijirou leaned in closer, looking through Aizawa-Sensei's hood. "Is your body hair red or–?"
"Kirishima!"
"It was just a question!" He said, holding his hands up in a placating gesture. His eyes moved down though, to the hem of his teacher's hoodie, focusing on the hairs of his arm.
It could have been a trick of the light, but for a second there Eijirou could have sworn he saw red.
He moved a little closer to see and–
A lot happened.
First, there was a hand in his hood, yanking him back from Aizawa-Sensei's arm.
Next, his left hand flew out and grabbed his teacher's forearm.
He then proceeded to trip over his own feet, falling forward towards Aizawa-Sensei. But before he could fall, he managed to grab a fistful of his teacher's hoodie to keep him upright.
It was for naught though, as it only sent him tumbling down with the man and his shopping bag in tow.
Eijirou groaned, somehow feeling worse about a small bash to the skull than he did the time he had to fight Monoma, who had stolen both Bakugou and Todoroki's quirks and subsequently wiped the floor with him.
He sat up, only barely aware of how his shopping bag and its contents were strewn across the ground.
See, he was occupied with something much more important right now. Like how his teacher's arm hair was red.
And if his arm hair was red, then down there would surely be red too. Eijirou wasn't sure how to feel about that. Was he disgusted because it was his teacher, or entertained that it was his teacher.
Aizawa-Sensei shifted from where Eijirou sat on top of him, and he was foolish enough to believe that his teacher was simply telling him to get off.
The next thing he knew, there was another jab of pain – this time in his shoulder – as he was thrown off his teacher's back and onto the tiled floor of the shop again.
But Eijirou was determined to make sure he wasn't seeing things, so he pushed off the floor and tackled his teacher — who was slowly regaining his footing — to the ground again. He tore the hem of his sleeve back until Aizawa-Sensei's forearm was exposed.
"I WAS RIGHT!" He shouted in victory, "You do have red body hair."
And it wasn't even ginger, it was the same fire engine red colour as his own — dyed — hair.
And Aizawa froze for a moment.
And then he fled.
But before that though, he yanked on Eijirou's hood until his hair — and the dark balck roots beneath the red — were exposed.
Eijriou was helpless to stop Aizawa's escape, too busy clawing at his hood and pulling it back over his head, hoping nobody saw his hair.
"I'm gonna tell everyone you have red pubes!" Eijirou shouted into the shop, hearing a clatter as Aizawa-Sensei paid for his items and got the fuck out of there.
An employee with white hair and black horns stared at him from across the aisles, looking exhausted. Eijirou blushed, the smile he gave them looking more like a grimace.
"We know each other." He explained, but the worker just kept standing there, staring at him with dead eyes.
Right, well Eijirou had shit to do today, like dye his hair.
He picked up his shopping basket and began refilling it with items before making his way to the counter to pay.
Thankfully, none of the employees mentioned the embarrassing scuffle, nor the pitch black roots of his hair which they could most definitely see.
He slipped through the doors of the shop and made his way back to UA.
His hair wouldn't dye itself after all.
Eijirou applied the brush to his scalp again, lightly moving it along the strands of hair until every black piece was covered in bright red dye.
The song on his phone changed, and his face lit up as he heard the quick drum beats.
Holding up the brush to his face, he sang into the makeshift microphone.
"You're so hot, teasing me!" He pointed at himself in the mirror, over-acting the words to the point where he was practically flirting with himself.
"So you're blue, but I can't take a chance on a kid like you." He smirked at his reflection, music blasting from his phone's speaker until he couldn't hear his voice over the singer. "It's something I couldn't do!"
Eijirou slid out through the open bathroom door and out into the empty house, his mothers having gone out for 'Date-Night', leaving him with an empty house.
Other kids might be tempted to hold parties when their parents were out of the house but Eijirou wasn't like other guys. His hair was in dire need of dying, and he couldn't bare to leave it another day.
"There's that look, in your eyes." He walked down the hall, throwing himself against one of the door frames and leaning against it like one of those woman from those really old films. "I can read in your face that your feelings are driving you wild. Oh, but boy you're only a child!"
He sprung off the wall, strutting down the corridor and out into the landing where he broke into the chorus. Eijirou moved his body to the choreography, pretending to playfully flirt with Monoma the bartender as though he were actually in Mamma Mia.
The chorus ended, running into an instrumental break where Eijirou slid down the banister, still in character and flirting with his imaginary partner.
He came to the end of the stairs and hopped off, walking slowly towards the centre of the room where he continued to do the choreography, slightly breathless from the effort he was putting into his performance.
"I can see," Eijirou moved towards a spot on the wall, like a wildcat stalking its prey, "What you wan–"
A knock came from the door, making Eijirou jump, a small squeal of surprise leaving his lips.
He froze, mind telling his body to shut down and pretend like he wasn't at home. But the knocking started up again, harder this time, more desperate.
Shit, what if the person at the door was here to kill him? An axe-murderer or his estranged evil twin who'd been stolen at birth, back to enact his revenge.
Eijirou began pacing the floor, the knocking only growing louder until he couldn't take it anymore.
He fled the hall, running to the living room instead where he picked up a poker from the fire, brandishing it like a weapon. At no point did it occur to him that he could use his quirk, or to, y'know, call the police
Creeping closer to the door, berating himself for not turning off the music that was still blaring throughout the house, he held the poker higher until he could throw it like a javelin. Yeah, that way he could yet it at the intruder and then get the fuck out of there
The knocking was louder now, practically shaking the door in its frame. Eijirou winced, hoping the killer would stop soon. He was too young to die!
"Kirishima I swear to fuck, if you don't open this door right now, I'm telling Hatsume that you're willing to be a test subject for her inventions."
Eijirou jumped at the voice, launching himself at the door and ripping it open, caution thrown to the wind.
It swung open, Eijirou quickly making use of the space by bringing the poker up to the potential-maybe-a-thief-maybe-a-killer-maybe-both-possibly-neither, and holding it against his throat.
The dark lighting made it difficult to see who was standing there, but when Eijriou moved forward, his eyes adjusted to the the low light.
"Aizawa-Sensei?" He asked, more than a little surprised at the presence of the other man.
His teacher brought his hand up, pushing the poker away from his throat, only letting a short "yes" pass the boundary of his throat.
"What are you doing here?"
Aizawa was silent for a moment, allowing Eijirou to take in what he was wearing. His fashion sense was obviously non-existent, because no one wears tight fitting pink tracksuit bottoms with a brown t-shirt. And a blue bucket hat? Really?
Also what the fuck? He'd literally seen the man earlier that night and here he was, wearing completely different clothes?
The man mumbled something into the cold night air, but Eijirou didn't catch it.
"What?"
Another mumble.
"I literally can't hear you. What are you on about–
"I need you to help me with my roots!" Aizawa shouted, pulling the bucket hat off his head and revealing the bright red hair growing from his scalp. Suddenly, his eyes widened, as if only just realising what he'd done.
Eijirou gasped, dropping the poker on the doorstep and dragging Aizawa — who was frantically looking around to see if anyone else had seen his hair — inside.
"Of course I'll help!" He said, bringing the man up the stairs towards the bathroom where he'd just done his own roots.
"... thank you." Aizawa replied, eyes flitting sound to take in every little detail of Eijirou's home.
"No problem!" He grabbed a brush and a small mixing pot from under the sink and rifled through Aizawa's bag until he found the black dye.
"I have to ask though, who usually does your roots if you can't do them yourself?
Aizawa blushed at that. Fucking blushed.
"That doesn't matter. He's out of town anyways, so he wouldn't have been able to help."
Eijirou gaped a little, jaw hanging wide open at the man's words. And that's when it dawned on him. A man who was close with Aizawa, close enough to know about his hair and willingly help him everytime he had to dye it. A man who Aizawa blushed at the mention of, who was obviously a big part of the other man's life.
He gasped then as the dots all came together.
"It's Mic-Sensei! Mic-Sensei helps you dye your hair!" Eijriou shouted out, mind running a mile a minute, thoughts racing by too fast to be coherent.
His teacher blushed harder, shoving his face between his hands and twisting away from Eijirou.
A glint of metal caught his eye in the mirror and he turned, just in time to see Aizawa's left hand slip over his eyes.
Aizawa's left hand which, on one if his fingers was a silver wedding band with– was that sheet music? embedded in the metal?
He let out a gasp of excitement, squealing as the last dot connected. As the pin dropped and came to rest on the floor.
"YOU'RE MARRIED TO MIC-SENSEI!?"
His teacher's blush — which Eijirou honestly didn't think could get any worse — grew and strengthened until he was practically purple in the face.
Eijirou reeled back in his excitement, knowing he was about to win a lot of money with this information. He knew Aizawa was gay, and even then he was smart enough to know what the man was with Mic-Sensei. Did it make sense? No. Is that why Eijirou actually picked it? Yes.
After a few moments of silence — relative silence, Does Your Mother Know was still blasting through the house at max volume — where Eijirou mixed the black dye in his little bowl, spreading it evenly until the colour was smooth throughout.
"Were you listening to the Mamma Mia soundtrack before I came in?" His teacher asked, still recovering from his blush, a slight flush on his cheeks being the only evidence that it happened.
"Obviously. What else would I be listening to?" Eijirou asked the man, beginning to section his long hair — Gods above, it was so silky? It was like the softest blanket in the world, wrapped in little strands around his hand — and prepared for the dye.
"How do you feel about Into The Woods?"
Eijirou smiled at his teacher through the mirror, his grin matching the maniacal twist of Aizawa's lips.
It became tradition then, for Eijirou and Aizawa to get together and help one another dye their hair, singing along chaotically to musical scores as they did.
And when Eijirou listened to Aizawa's relentless advice and finally got with Monoma, he invited him to such a night. And Aizawa invited his loud blonde too.
And it became tradition once more, though there were many more mishaps and a lot of exciting discoveries, like how Monoma could grow red hair if he copied Aizawa-Sensei's quirk.
Those made for some interesting pictures. And great blackmail.
Something they also, unfortunately, learned was that Aizawa liked to tell stories. To tell mortifying stories about Eijirou. To tell mortifying stories about him to his boyfriend.
Eijirou could dye from embarrassment.