The main character is just an average student. But he doesn't like PE because his dick soon gets erected when he sees a girl in swimsuit or wearing bloomers. Misaki, a sick-room teacher, knows it and tries to solve his concern. But how...? To reduce his sexual desire, she decides to make him ejaculate before a PE class. Also, Honoka, his classmate, joins them and the story gets more complicating and erotic....