All performers are adults in this forbidden mother-and-son role-play. Riori is a mother in her fifties whose husband treats her like a housekeeper, while her adult son cannot bear to see her suffer. Once his wedding is arranged, loneliness drives her to clutch his underwear and masturbate every day. On the day he is due to leave home and live with his fiancée, Riori can no longer suppress her hidden desire and seduces him.