Katsuki + prompt ⁵⁹⁾ “…that’s not mine.” gn
You walked into your shared apartment with a small, neatly wrapped box tucked behind your back. Katsuki was sprawled on the couch, one arm slung over his face, freshly showered from an intense training session. His hair was still damp, spikes slightly less aggressive than usual.
"Happy birthday, Blasty." you teased, stepping closer.
A grunt.
"Tch. It’s just another day."
"Here." You rolled your eyes but didn’t argue. Instead, you held out the box.
"That’s not mine."
Katsuki cracked one eye open, then sat up with a skeptical look.
You snorted.
"Uh, yeah, it is. I literally wrapped it for you."
He eyed it suspiciously, as if the box might explode in his hands—which, given his quirk, was ironic. But after a beat, he took it, fingers brushing yours. His ears tinted pink as he tore the paper off with the same efficiency he used in battle.
Inside was a simple keychain—small, metal, and engraved with a tiny but unmistakable “Dynamight's No. 1 fan - <3 Y/N” Not flashy, not over-the-top, just… something to keep with him. Something from you.
Katsuki stared at it, expression unreadable. Then, in a rare moment of quiet honesty, he muttered, "...Thanks."
You grinned. "Told you it was yours."
He huffed, slipping the keychain into his pocket like it was no big deal. But the way he refused to look at you straight on, the way his fingers curled protectively around it for just a second too long—you knew it meant everything.
"You’re such a pain," he grumbled, shifting his weight as if already regretting the soft moment.
But then, in a move so quick you almost missed it, he tugged you down onto the couch beside him. His arm draped around your shoulders, warm and firm, holding you there like it was the most natural thing in the world.
Your heart skipped. "Katsuki—"
"Shut up. Just sit here for a sec."
You bit back a smile, leaning into him. "Happy birthday, Katsuki."
He exhaled sharply, resting his chin against the top of your head. "Yeah, yeah."
A pause.
Then, so quiet you barely caught it—
"It is now."
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