​Ryuuichi’s first sexual encounter leaves him traumatized and unable to maintain an erection. Desperate for a fresh start, he takes up the job of a janitor at a girls’ high school. However, Ryuuichi’s poor work ethic leads to imminent dismissal. Just when he’s at his lowest, he encounters Midori, and to his surprise, he experiences an erection while conversing with her. Consumed by his overwhelming desire, Ryuuichi commits a heinous act and rapes her. Realizing he has limited time left at the school, Ryuuichi resolves to spend his remaining month engaging in a spree of sexual assaults on the unsuspecting students.​