Izuku didn't mean to notice things about Kacchan, but his brain never turned off, and since he's always been so in tune with Kacchan's mannerisms… It's come to that when things become slightly off, it's a blaring alarm in Izuku's head.

And this alarm has never turned off since everyone moved into Heights Alliance.

It started on moving day.

When he and Kacchan ended up in the same elevator ride, both carrying obscenely overfilled boxes, he heard the blonde scoff.

That's when Izuku realized this was one of the boxes of his All Might merch collection. Specifically, all his clothes that were All Might themed. He squeaked, slightly embarrassed.

"I- I- It's just like, my room at home-"

"I don't give a fuck, Deku."

The elevator dinged, and he hopped off the elevator. He turned around to nod goodbye to Kacchan, but the box in the blonde's hands caught his eye.

A countdown looking flap, with the number 934 on it, and two picture frames.

The elevator closed before he could get a closer look.

934…?

The next day, Kacchan lost his key card.

Izuku didn't mean to realize it, but he did.

Kacchan exclusively hung out with at least one other person outside of the dorms, a rarity for him, and hung out in the back, not leading the pack as he usually does. He went to the gym with Kirishima (not a rare thing), but waited for him to leave even though the red head was 15 minutes late.

Extremely strange.

The final nail on the coffin was actual confirmation.

Izuku didn't mean to hear this, but he was talking to All Might when Kacchan walked into the faculty lounge. He also didn't mean to hide behind the teachers' desks but… call it instinct.

"Yes, Bakugou?"

"I broke my keycard while moving."

A pause.

"How could you possibly break-"

"Snapped in half."

Izuku could feel Aizawa's narrowed glare.

"Did you lose it? Or did it break?"

Kacchan would never just lose anything.

"Is there a difference?"

"If you lost it, I will have to go through the process of deactivating it manually from the school's system. It's an incredibly long process, with a risk of messing up the whole system. We'd like to avoid having to deactivate cards–especially of our Hero students."

A pause.

"I broke it."

Another pause.

"I'm deciding to trust you on this. Don't make me regret it. I'll issue you another one tomorrow morning."

"Thank you, Sensei."

Yet another thing–

Thank you, Sensei.

Kacchan sounded… relieved.

Thank you…

Still, Izuku kept his distance. He kept these observations in his mind, rattling around in the distance. As much as he wanted to dissect Kacchan's actions more–he was busy.

The alarms still went off, but they were quieter. Ignorable.

Sure, Kacchan checked his phone a little more often.

Sure, there were a couple poker games where Kacchan would shove his copious winnings into Kirishima's hands when he thought no one was looking–a silent look between them that Izuku oh so wished he knew the meaning of.

Sure, sometimes an image, like when Uraraka bruised her face, or an act, like when Mina tried to get Kacchan to try on mascara, would cause a certain look to pass over Kacchan's face.

But never anything more than a second.

Never anything more than a passing moment.

Regardless, Aizawa had spared no time getting them back into the thick of things. The provisional licensing exam was right around the corner. Izuku filled his days to the brim–running in the morning, studies during the day, training in the afternoon, and technique practice at night.

Soon enough, the test came.

He passed. Kacchan didn't.

Next thing Izuku knew, he was fighting Kacchan on Ground Beta.

"Don't worry about me! FIGHT! What the hell is wrong with you?!"

The fight was about many things–All Might, guilt, their troubled past. Izuku thought this was the final layer to Kacchan.

He'd finally peeled back the final layer. Finally was able to clear the misty fog that clouded their relationship.

Finally, he thought, they could move forward.

"Kacchan?" Izuku called out, unsure of the sight in front of him.

Three days, house-arrest.

Simple.

Just clean up the dorms, do the chores, and reflect on the fact that he had broken into restricted school grounds on a night that he should've been celebrating to fight with his childhood rival.

Slow days, but simple days.

"The fuck do you need nerd? Can't figure out how to get a vacuum to work?"

In front of Izuku sat a little girl–no older than 6–with stunning blonde hair, round brown eyes, and the smallest frame he's ever seen on a child. A black oversized hoodie dwarfed her, making her seem even tinier.

"N-No…"

Alarms were blaring in his head.

A shimmer of makeup glimmered on the girl's face as she rubbed her cheek with the back of her hand. Her hair was in an elaborate updo–braids running to the back while white bows held her hair up in ponytails.

She sat on one of the couches near the entrance, staring down at a green ID that was on a lanyard around her neck. Izuku looked a little closer–it was a Heights Alliance Key Card.

"Hah?! Are you not vacuuming?! I swear…"

The girl perked up at Kacchan's voice; a smile danced on her lips. The ID fell from her hand, the front side facing out. She stood up, brown eyes wide.

Izuku blinked, eyes matching hers.

The ID card read–

Bakugou Katsuki. Class 1-A. Hero Course.

"DEKU!" Kacchan yelled, his stomping getting louder. "Stop ignoring me!"

Izuku was suddenly taken back to a certain memory from early middle school.

"Izuku, honey." His mother stood in the doorway in her scrubs. "Mitsuki has unexpectedly gone into labor. It's a little early, but nothing to really worry about."

Izuku was… really confused. "Labor? She…"

"Oh, dear. I forgot that you had drifted from Katsuki. But yes! Mitsuki is expecting another child! I was going to offer to drop you off at the Bakugous' house since Katsuki…"

"Katsuki?" the girl whispered.

Izuku grasped at the memory–trying to remember more.

"Oh, Izuku! It's a girl! Oh she is just so adorable! Now how do I get this FaceTime thing to work…"

"DEKU! If I get there and you're standing there doing jackshit I'm going to-"

"Her name? Oh it really is so adorable–if Katsuki had been a girl they would've named him this! Oh, Katsuki's going to be such a great older brother! Her name is…"

The words fall from Izuku's lips, unbidden.

"Miska."

The girl's face whipped towards Izuku, surprise covering her tiny features.

Kacchan stood, frozen across the room, his mouth slightly ajar.

Both of their blonde hair reflected the living room's light in the same way.

Izuku swallowed.

"Kacchan… your sister's… here?"