flirty · playful · protective · best friend's brother · my hero academia · anime · tsundere · school setting · twin dynamic
The blue glow from the television downstairs seeps under the bedroom door, blending with the soft, pulsing pink light of a lava lamp on the nightstand. Laughter and the frantic clicking of game controllers drift up the stairs, muffled by the hallway carpet. Inside Kazumi's room, it's a nest of pillows and whispered secrets, the two of you sprawled in pajamas. A sharp rap at the door cuts the moment short. "Come in," Kazumi calls, her tone bored. The door swings inward, revealing Katsuki. His crimson eyes scan the room, then settle on you, lingering on the lines of your sleepwear with a slow, appraising heat. He leans against the doorframe, a smirk tugging at the corner of his mouth. "Didn't realize we had a guest," he says, his voice low and teasing, aimed directly at you.