Chapter Text
Midoriya Izuku and Bakugou Katsuki hated each other.
That was, quite possibly, the most universally agreed upon fact in Class 1-A.
They argued constantly. They snapped at each other over nothing. Katsuki yelled, Izuku shot back (which was new, and frankly concerning), and the rest of the class had long since accepted that whatever was going on between Izuku and Katsuki was—
“—not normal,” Kaminari whispered, watching as Bakugou slammed his hands onto his desk.
“Shut up, Zu.”
Izuku didn’t even look up from his notebook.
“Make me, Kats.”
Silence.
A very specific kind of silence.
The kind where twenty teenagers slowly turned, in perfect unison, to stare at them.
Izuku blinked. “What?”
Uraraka tilted her head. “...what did you just call him?”
Bakugou scowled immediately. “None of your business.”
“That didn’t answer the question,” Iida said, already doing that chopping motion with his hands like he was trying to karate the confusion out of the room.
Izuku finally seemed to realise something had gone wrong.
“Oh. That.” He waved a hand vaguely. “It’s just—uh—a nickname.”
“For him?” Mina leaned forward, eyes sparkling with the exact kind of energy that meant this was about to become everyone’s problem. “You have nicknames for each other?”
“No,” Katsuki snapped at the exact same time Izuku said, “Yeah.”
They paused.
Looked at each other.
“Shut up.”
“You shut up.”
“Don’t tell me to shut up—”
“Then stop talking—”
Aizawa’s capture weapon snapped out and wrapped around Katsuki and Izuku.
“Stop.”
Immediate silence.
Aizawa stared at them with the exhausted resignation of a man who had made several poor life choices that had somehow led him here.
“Take it outside if you’re going to argue like that.”
“They started it,” Katsuki muttered.
Izuku snorted. “You always say that.”
“You always start it—”
The capture weapon tightened.
“Outside,” Aizawa repeated.
They did not take it outside.
Instead, Izuku and Katsuki sat back down, still glaring at each other, like the argument had simply been… paused.
Not ended.
Paused.
“That’s not normal,” Kaminari said again, more confidently this time.
“Lots of people have nicknames,” Izuku said, flipping a page in his notebook.
“Yeah,” Sero agreed slowly. “But usually not like… that.”
“What’s wrong with ‘Kats’?” Izuku asked.
Bakugou made a noise like he’d just swallowed something offensive.
“What’s wrong with ‘Zu’?” Kaminari shot back.
Izuku opened his mouth.
Paused.
“…nothing,” he said, a little too quickly.
Mina slammed her hands on her desk. “Okay, no. No, something is up.”
“There is nothing up,” Izuku said.
“There is absolutely something up,” Kaminari said.
Todoroki, who had been silent this entire time, finally spoke.
“Are you secretly related?”
The room went quiet.
Izuku choked.
Katsuki froze.
Everyone leaned in.
“…no,” Izuku said.
“…no,” Katsuki said.
At the exact same time.
Same tone.
Same speed.
Aizawa sighed.
“I’m going to regret asking this,” he muttered. “But why do you both sound like you rehearsed that?”
“We didn’t,” Izuku said.
“We didn’t,” Katsuki said.
Another pause.
Another look.
“Stop copying me.”
“I’m not copying you—”
“Shut up—”
“Make me—”
The capture weapon snapped out again.
Lunch did not improve things.
If anything, it made things worse.
Because now everyone was watching Izuku and Katsuki.
Not subtly, either.
Blatantly.
“They’re acting normal,” Kirishima whispered.
“They always act like this,” Kaminari whispered back.
“Exactly,” Mina hissed. “That’s the problem.”
Izuku sat cross-legged on the bench, scrolling through his phone.
Katsuki leaned back in his chair, arms crossed, looking like he’d rather be anywhere else.
Izuku’s phone buzzed.
He glanced at it.
Paused.
Then—
Snorted.
Actually snorted.
“What?” Uraraka asked immediately.
“Nothing,” Izuku said, already typing.
Katsuki’s phone buzzed.
He checked it.
Scowled.
“Tell them to shut up.”
“I’m not telling them that,” Izuku said.
“Then I will.”
“You literally can’t, Kats, you’re in the chat.”
The entire table went still.
“…the chat?” Kaminari repeated.
Izuku froze.
Katsuki closed his eyes.
Slowly.
Like he was counting to ten.
“What chat?” Iida demanded.
“No chat,” Izuku said quickly.
“There is absolutely a chat,” Mina said.
“There is not a chat,” Izuku insisted.
Katsuki grabbed his phone, typed something aggressively, then slammed it face down on the table.
Izuku’s buzzed again.
He looked.
Winced.
Kaminari lunged.
Izuku yanked the phone away just in time.
“Nice try.”
“I saw that,” Kaminari said. “There’s a group chat.”
“There isn’t.”
“There is.”
“There isn’t.”
“There is.”
“Eat your lunch,” Aizawa said from behind them.
No one had seen him sit down.
Everyone shut up.
Immediately.
Izuku glanced back at his phone.
Another message.
He hesitated.
Then—very deliberately—tilted the screen away from everyone and typed.
Katsuki kicked him under the table.
“Don’t.”
“I’m not saying anything!”
“Don’t even hint at it—”
“I’m literally just replying—”
“What did you say?” Mina demanded.
“Nothing!”
“You’re smiling,” Kaminari pointed out.
“I am not smiling.”
“You are absolutely smiling.”
Izuku wiped his face like that would somehow fix it.
“I’m not smiling.”
Katsuki leaned over, trying to see the screen.
Izuku shoved his face away.
“Personal space.”
“We don’t have personal space,” Katsuki snapped.
That.
That was the moment.
Because that was not—
That was not a thing people who hated each other said.
That was a thing—
“…you share personal space?” Uraraka asked slowly.
“No,” Izuku said.
“Yes,” Katsuki said.
They both paused.
“Oh my god,” Kaminari whispered. “What is happening.”
Izuku stood up abruptly.
“I’m going to get water.”
“You have water,” Katsuki said.
“I’m getting more water.”
“You’re avoiding the question—”
“I’m hydrating.”
“You’re lying—”
“I’m not lying—”
“You’re always lying—”
“I am literally the worst liar here—”
“That’s not saying much—”
“Shut up, Kats—”
“Make me, Zu—”
Silence.
Again.
Aizawa stood up.
“I’m leaving.”
“You just got here,” Sero said.
“I’ve heard enough.”
“That’s fair,” Kaminari said.
It got worse after lunch.
Because now everyone was watching Katsuki and Izuku more closely.
Every little thing.
Every interaction.
Every glance.
Every—
“Oi.”
Izuku looked up.
Katsuki tossed something at him.
He caught it without thinking.
Didn’t even look.
Just—caught it.
Like it was normal.
Like Izuku had done it a thousand times before.
“…what was that?” Kirishima asked.
“Pencil,” Izuku said.
“You didn’t even look,” Mina said.
“I don’t need to look.”
“Why don’t you need to look?”
Izuku blinked.
“…because I have hands?”
“That’s not an answer,” Kaminari said.
Katsuki clicked his tongue. “You’re all idiots.”
“WE’RE the idiots?” Mina said. “You just threw something at his head and he caught it like it was scripted—”
“It wasn’t at his head,” Katsuki said.
“That’s not better!”
“It was to his left.”
Everyone paused.
Slowly turned.
Izuku nodded. “Yeah, that’s where it was.”
“…how did you know that,” Kaminari asked.
Katsuki frowned. “Because I threw it.”
“No, I mean how did you know he’d catch it?”
Katsuki looked at Izuku.
Like the answer was obvious.
“Because it’s Zu.”
Silence.
Again.
Todoroki leaned forward.
“I am more convinced than ever that you are related.”
“We are not related,” Izuku said immediately.
“We are not related,” Katsuki echoed.
Same tone.
Same speed.
Same—
Aizawa stood up again.
“I am taking a nap.”
“You just woke up,” Sero said.
“I am going back to sleep.”
“That’s valid,” Kaminari said.
The last straw came at the end of the day.
Because of course it did.
Because nothing about this day had been normal.
“Izuku,” Iida said, adjusting his glasses with the kind of intensity that meant he had been thinking about this for far too long. “I would like to ask you a direct question.”
Izuku froze halfway through packing his bag.
“…okay?”
“Are you and Katsuki hiding something from the class?”
“Yes,” Katsuki said immediately.
“No,” Izuku said at the exact same time.
They both stopped.
Looked at each other.
“You’re so bad at this,” Katsuki said.
“You just said yes!” Izuku hissed.
“Because we are!”
“We are not—”
“We literally are—”
“That’s not what he meant—”
“Then what did he mean—”
“I don’t know—”
“Exactly—”
“Stop talking—”
“You stop talking—”
“Make me—”
“Gladly—”
“Try it—”
Aizawa dragged a hand down his face.
“I’m transferring one of you.”
“No you’re not,” Izuku said automatically.
“No you’re not,” Katsuki echoed.
Aizawa paused.
Slowly looked at them.
“…why did you both say that.”
Izuku froze.
Katsuki went very, very still.
And for the first time all day—
They looked like they’d actually made a mistake.
A real one.
The class leaned forward.
Because finally.
Finally—
Something was about to make sense.
Katsuki clicked his tongue.
Izuku swallowed.
And somewhere, in Izuku’s pocket—
His phone buzzed