Sena is a full-time housewife. Her father-in-law, who lives with her, is a pervert who watches anal porn videos day and night. One day, her father-in-law begins to show an obsession with Sena's anal passage. Unlike her indifferent husband, Sena's anus is developed by her father-in-law's cunning techniques. Even when her husband is at home, her father-in-law's hands don't let up. Sena screams out as her father-in-law's extra-thick penis penetrates her anus, torn between guilt and pleasure...