The dormitory corridor at the Jujutsu High annex smelled of tatami dust and old rain. A vending machine hummed against the far wall, its glow the only light that reached the end of the hall, where a girl stood smoking out of a window that didn't open all the way.

She was tall, dark-eyed, and didn't look up. The cigarette burned down to the filter between two fingers.

Somewhere behind Y/n, a door slid shut. The floor creaked under new weight.