An estranged son returns home with his wife Mahiro after falling on hard times. The father reluctantly lets them stay but constantly insults Mahiro and criticizes everything she does. When she reaches her limit, she summons him to a dark room. There he discovers that his daughter-in-law is actually the terrifying, irresistible dominatrix from the BDSM club he has secretly visited for years—the mistress who knows his humiliating pet name and immediately puts him back under her control.