Asahi, a wife, was living a happy life with her kind husband, having bought her dream home. However, her husband suddenly suggested that she move in with her father-in-law... Asahi had never really liked her father-in-law, and was troubled at first, but after her husband strongly persuaded her and explained that her father-in-law lived alone after losing his mother-in-law, she reluctantly agreed to live with him. However, this is where the nightmare began... Asahi, who was not satisfied with her nighttime activities with her husband, was accidentally seen masturbating in the living room by her father-in-law. Taking advantage of this weakness, her father-in-law began to play sexual pranks on Asahi, and the pranks gradually escalated. Asahi resisted at first, but her father-in-law's skillful training captivated her both body and mind...