A man who desires to be cuckolded by his mother-in-law consults a sex massage therapist, who then records the cuckolding scheme. The first target is his 37-year-old mother-in-law. She is given a free coupon at a massage parlor and happily accepts the treatment. As oil is applied to her body, she becomes entranced, offering no resistance when penetrated from behind, moaning in pleasure. She writhes in ecstasy, her chest flushing red with arousal. The second target is a 40-year-old mother-in-law. During a business meeting at a hotel, a sensual massage is performed. Wearing a blindfold, she has a penis inserted into her. Midway through, the client's son secretly takes the lover's place. Unaware of the switch, the mother-in-law reacts with intense, agonizing pleasure.