Students Tanaka and Yamada stay overnight at their teacher's house to study. They become infatuated with the teacher's wife, Natsumi, captivated by her beauty. At night, Natsumi seeks sex from her husband but gets rejected. She then masturbates in front of Tanaka, who secretly watches. The next day, Natsumi sneaks away to have sex with Tanaka. Taking advantage of her husband's sudden departure, Natsumi's insatiable lust is revealed as she ends up sleeping with both students.