It’s school festival day and Min-hyuk is busy dancing and singing. However, it is not the stage but a toilet that binds his destiny. He is bewitched by a daring high school girl, Mi-hyun, who comes into the men’s room because the women’s room is full. From that day on, Min-hyuk woos her, escorts her home at night, stuffs her locker with roses, and clears a passage for her in the morning after the snow falls. For all his efforts, he doesn’t get much more than a tender glance from Mi-hyun. When she suddenly vanishes, ‘sorry’ is the only word she leaves behind.