Living with her husband, who remarried, and his son Yoisho, stepmother Nana finds herself deprived of intimacy in her marriage. Sensing her loneliness, Yoisho begins to seduce her, leading Nana down the path of becoming his sex slave. Whenever her husband claims to go on a business trip, Yoisho invites his friends over, and Nana is repeatedly raped and tormented by the young boys. Gradually consumed by the pleasure, Nana loses herself in physical ecstasy, vividly exposing her shameless, lustful self.