Thread by @bakutiddys

#aibaku where they become friends with benefits but neither of them know how it happened

The first time they hooked up was at a school reunion party, five years after the class graduated. Katsuki hadn’t wanted to go, honestly, he thought it was all a waste of his time

But four seperate people checked with him to ask if he’d come and he didn’t want to deal with looking like an asshole if he ditched it

So he showed up reluctantly and made small talk for thirty minutes before sitting himself at the open bar to start plotting an escape plan

Three drinks in and he felt someone’s presence next to him, but when he looked up it wasn’t anyone he expected to see

“Didn’t think I’d see you here.” Aizawa stole the words right out of katsuki’s mouth, making him scoff i to his glass

“Could say the same to you.” Katsuki

Muttered. “I thought you’d be the first to ditch something like this.”

“Can’t disappoint my class like that can I?” Aizawa huffed and took a seat next to katsuki

“Not your class anymore.” Katsuki said pointedly. He glanced over and saw Aizawa staring at him with a weird

Expression that he couldn’t explain. So to stop himself from feeling awkward about it, he shoved a drink at Aizawa and then downed his own before ordering another

Everything after that was a blur, so katsuki had no idea how or why it happened— but at one point he blinked,

and when he opened his eyes again he found himself naked in a strange bed and a strange room, with his former teacher sleeping next to him

Also naked

“Fucking hell.” Katsuki muttered to himself

Somehow that small sound was enough for Aizawa to open his eyes and look at him

And then, without a word they were kissing and every forgotten memory came crashing back

The feeling of Aizawa’s hands on his body and the taste of his cum and the feeling of being stretched beyond what he thought he could handle

Before he knew what was happening he was being impaled again, this time with less burn and more urgency, and then aizawa was on top of

Him and the bed was shaking under them as katsuki fought to keep up with the rough pace the older man was setting for them

“Oh f-fuck! Fuck— why are you so— shit…” he stared up with wide eyes, already feeling his pleasure building and ready to tip over

“So what?” Aizawa asked pointledly — and somehow the old bastard wasn’t even out of breath. “What do you wanna say to me?”

Katsuki was too breathless to respond at that point, as his orgasm crashed over him like a wave and spread over his entire body — and aizawa’s clean sheets

“Fuck!” He yelled, completely unconcerned about being overheard by anyone

The bed kept creaking under them as aizawa moved and chased his own peak, and when he got to it he filled katsuki up until he felt too full to move, adding to the copius wentess already spreading between

His legs

“Holy hell.” Katsuki gasped, breathless and sweaty as aizawa pulled him into his arms. The gesture was surprisingly soft and completely unexpected

They laid in silence for a long while after that, listening to each other’s ragged breathing and unsteady heartbeats

“Are you okay?”

“What the hell was that?”

They spoke at the same time but katsuki ended up biting his tongue in regret. He glanced over his shoulder at aizawa and then shimmied until he was facing the older man

“How the hell did this happen?” He asked

Aizawa raised an eyebrow at him and his lips lifted into a half smile. “Well, I remember something about you challenging me to a spar and claiming I couldn’t keep up with you because I’m too old.”

Katsuki felt his eyes widen in shock and his face turn red “i said that crap? Fuck… I’m—“

“That, and then you invited yourself over here for dessert.” Aizawa said. “I thought that part was up for interpretation.”

“Oh.” He sighed and gulped, daring to glance up at Aizawa’s face

“You regret it?”

“No, I— I’ve kinda been fantasizing about this since second year. Never thought it’d happen though.”

Aizawa scoffed and leaned down so their lips were almost touching. “I’ve kinda been fantasizing about it since your second year too.” He admitted

After that it became a regular thing for them, whenever they crossed paths, to catch up — and that usually ended in one of their apartments with their clothes across the floor and their lips bruised from kissing for hours

It was a good deal in katsuki’s mind, somehow

But he never noticed when their touches started to linger beyond sexual, or when leaving before the morning became too much of a hassle, or when having a change of clothes at Aizawa’s place turned into having entire outfits in his closet and his own drawer in the dresser

He never noticed when they went from last names to first, and then to pet names and I love you’s before leaving for work

Somehow all of that snuck up on them, and then, without either of them noticing, it became more natural to come back to each other than to leave

And eventually they stopped leaving altogether, and decided staying was much better than always catching up anyway

[🖤🧡