Maya is a mother living with her only son, Shigeo. One day, Saito, a friend of Shigeo's from their elementary school days, comes to visit the house. Saito has always had a sexual interest in Maya, and when Shigeo isn't looking, he rapes her. Although Maya feels guilty about having sex with her son's friend, her body is aroused by the long-awaited sex with a young man. The actions of these men, who are at an age where they can't help but want to have sex, escalate day by day...