The earnest and innocent office lady, Iida Seiko, arrives from the countryside only to become a pet for a group of men after a staged bicycle accident. This third installment in the popular series focuses on trapping pure, young virgins and subjecting them to relentless, sadistic training. Forced to clean in nothing but gym shorts, she endures harsh treatment including anal training, deep throat, and erotic asphyxiation. She is urinated on, made to wear stockings over her head, and has graffiti drawn across her face—each act degrading her further into a submissive pet. Most notably, she's sent to a convenience store gagged with a mouth bit, dressed in a sailor uniform to buy cigarettes. Unable to speak, her failed attempt and awkward interaction with the clerk only heightens the men's sadistic pleasure. Her deeply humiliating transformation captivates viewers with its intense psychological and physical degradation.