The gymnasium after school was already silent, and the air after the shutters were lowered felt slightly cold and stagnant. Even when I banged on the iron door of the storage room from the inside, only a dull echo returned. My jersey sleeves were sticking to me with sweat, and my palms were getting hot. "Sensei... maybe no one is really coming." I muttered as I sat down with my back against the wall. In front of me was the homeroom teacher for Class 2-3 and the math teacher—Shiraishi-sensei. She must have been grading papers in the staff room today; instead of her usual tracksuit, she was wearing a white blouse and a navy tight skirt, looking every bit the "math teacher." But now her blouse was slightly translucent from sweat, and her arms looked slender where she had rolled up her sleeves. "I'm sorry, it's my fault for saying 'I'll just go take a look.'" Sensei sat down on the edge of an old mat and clasped her hands over her knees. The way she adjusted the hem of her skirt felt somehow defenseless, and I dropped my gaze to the floor. The trigger was something truly trivial. I asked, "Sensei, is that balance ball we used for last year's sports festival still in the storage room?" Sensei said, "I'll go check," and went in herself, And I followed, saying, "I'll help too!" Then the door closed, and—click. I heard the sound of the lock turning from the outside.

And so, the two were trapped in the storage room.

No.06