“Whose birthday is it today?” You slipped up behind him, arm draping over his shoulders like you owned the space there. Katsuki barely paused mid-step toward Class 3-A, just cut his eyes at you with that sharp, irritated glare that could peel paint.
“Shut up.”
You rolled your eyes, grin only stretching wider as you leaned closer, your breath ghosting his ear on purpose.
“I can start singing, you know…”
“Try it.”
“Come on, don’t be a pain in the ass for once, just today.”
“You’re the damn pain in my ass.”
You opened your mouth to snap back, already loading the insult, when the hallway exploded with noise, Kirishima, Midoriya, Denki, and half the class bursting out of nowhere with gifts, confetti, way too much enthusiasm. Katsuki’s reaction was immediate, loud, sharp, drowning them out entirely as small blasts cracked in his palms.
You winced. Yeah. There went your hearing.
He’d grown up, at least, technically. Birthdays didn’t hit the same anymore. As a kid, yeah, he liked the attention. Now? It crawled under his skin, made his shoulders tense, his jaw lock.
Still he didn’t walk away.
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The scrap of paper hit his desk with a soft flick.
Katsuki frowned instantly, muttering under his breath as he glanced back, and there you were, chin propped on your hand, that stupid, knowing smirk already waiting for him.
He groaned quietly, dragging the paper closer.
Birthday lunch for my boom boom?
His eyes rolled so hard it was almost impressive. He scribbled fast, sharp, no hesitation, and flicked it back.
Eat shit.
You stared at the back of his head, lips pressing together before you huffed softly and wrote again.
Come on! I know you love me
He paused this time.
You saw it, the slight stiffening of his shoulders, the way his pen hovered just a second too long. He wrote something quick, stopped, scratched over it, then wrote again.
Kys.
Yeah, I do
You bit back a smile, folding the paper like it meant nothing.
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“C’mon, bro, we have to celebrate.” Kirishima clapped his hands hard enough to rattle the table.
“Yeah! You’re not just skipping it, right?” Denki leaned forward, already pouting. Sero nodded like backup support.
“I’m telling you, Mina definitely planned something huge.”
“Of course I did!” Mina beamed. “Down to every detail. Jiro, you’re in too, right?”
“Obviously. As long as Denki doesn’t repeat what happened at Sero’s…”
“Oh, shut up.”
The noise piled on, overlapping voices, laughter, chaos, and in the middle of it, Katsuki just kept eating, calm like the storm wasn’t even worth acknowledging. When he finally looked up, it was with that flat, unimpressed stare.
“I’ll blow your heads off instead of confetti. Got it?”
Collective groan.
You slid a little closer under the table, reaching toward his plate without asking, fingers just barely brushing the edge before his knee knocked into yours.
“What?” you squinted.
He squinted back.
Then, without a word, he shoved the plate slightly toward you.
“You could’ve just asked, idiot.”
His thigh pressed against yours under the table, solid, grounding, and you couldn’t help the small smile that slipped out.
“Then maybe…”
“Say one more thing about my birthday and you’re dead.”
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“I swear to fucking…”
“Relax. I promised, nothing loud.”
You were walking ahead of him now, fingers laced tightly with his, tugging him along. He grumbled the whole time, gaze low, shoulders tense, but his grip didn’t loosen. If anything, it tightened when you stumbled slightly.
“Idiot. Why’re you rushing?”
“Don’t ask dumb questions.”
He followed anyway.
Of course he did.
You stopped in front of your door, turning to face him with a grin that already gave too much away.
“Close your eyes.”
“No.”
“Fine, I’ll do it for you.”
“Fuck, no.”
He exhaled sharply, jaw ticking, then shut them himself.
You smiled, softer this time, opening the door and guiding him in carefully, your hands coming up to cover his eyes anyway.
“I said I closed them.”
“This is for effect.”
A quiet click of his tongue, but he didn’t fight you.
“Okay, ready?”
You leaned in just a little, voice dropping.
“Three… two…”
You pulled your hands away.
“…one.”
His eyes opened.
And for a second, just a second, he froze.
“Ta-da.”
The cake wasn’t perfect. Not even close. The orange frosting had slipped slightly to one side, the lettering smudged where the heat of the candles softened it too much. The little explosions you’d tried to draw looked… questionable at best.
But it was yours.
“I know, I know, it’s not exactly…look, the guy in the video said it’d turn out better, and the comments were really convincing, so…”
He leaned forward and blew the candles out.
Just like that.
Your eyes widened.
“You didn’t even make a wish…”
“I did.” His voice cut in, low, steady. “While you were mumbling.”
You opened your mouth…
And his hand caught your chin.
Not rough. Not soft either. Just firm. Certain.
It stilled you instantly.
Then he leaned in.
The kiss wasn’t rushed. Not messy. Not desperate.
It was slow.
Deliberate.
Like he wasn’t trying to take something, but hold onto it.
His lips pressed against yours with quiet insistence, tilting slightly, adjusting like he had all the time in the world. Your breath caught somewhere halfway through, fingers curling instinctively into his shirt as he deepened it just enough to make your head spin.
There was heat there, but not the explosive kind he carried everywhere else.
This was steady.
His thumb shifted slightly against your jaw, grounding you, while his other hand hovered just close enough to your waist like he was deciding whether to pull you closer or keep the distance exactly like this.
You felt it, the way he lingered. The way he didn’t rush the moment.
Like he was saying something he wouldn’t say out loud.
When he pulled back, it wasn’t far. Just enough for your lips to part, your breath uneven. He brushed a quick, almost absentminded kiss to the corner of your mouth, like a habit he hadn’t realized he’d picked up.
You blinked, trying to catch up.
“You didn’t even try it yet.”
“About to.”
“I still haven’t given you the real gift.”
His eyes narrowed slightly, a hint of something amused flickering there.
“The real one?”
A small smirk tugged at his mouth. “That wasn’t enough?”
“It’s just a cake.”
“You made it.”
“And?”
“That’s enough.”
You stilled again.
Because the way he looked at you, it wasn’t teasing. Wasn’t sarcastic.
It was full.
Too full.
Like you’d handed him something bigger than you meant to.
“Try it first,” you muttered, softer now. “What if it tastes like shit?”
He shrugged, already reaching for the knife, movements careful, more careful than he’d ever admit. He cut a piece, steady, precise, then lifted it toward you instead.
“Eat.”
You raised a brow.
He didn’t budge.
So you did.
You chewed slowly, watching him the whole time, waiting for his reaction more than your own.
“Well?”
“It’s actually good.”
A quiet hum left you, surprised.
He smiled, small, but real, and set the fork aside.
Then leaned in again.
This time quicker.
You pushed at his chest lightly. “Seriously.”
He laughed under his breath against your lips before pulling away, tongue brushing briefly over his own like he was tasting both the cake and you.
“Yeah. Not shit.”
You rolled your eyes, smacking his shoulder, but he caught your wrist easily, tugging you closer until there was no space left between you.
“Thanks, dumbass.”
His forehead pressed to yours, breath warm, steady. Your expression softened without you meaning to, thumb brushing lightly over the scar on his cheek.
“Yeah, yeah. Happy birthday, boom boom.”
A pause.
“Now let go. I still have your actual gift.”
His grip didn’t loosen immediately.
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