Mayoko is a daughter-in-law living with her father-in-law at his house. Her father-in-law, who lost his wife in his youth, is an erotic novelist but has been struggling with poor sales lately. Reluctantly, Mayoko decides to use her own body as a model for his erotic novels to help him out… While trying to conceive a child with her husband, she is subjected to anal training by her perverted father-in-law in various places around the house, such as the living room, kitchen, bathroom, and even the toilet. Mayoko not only loses her anal virginity but also transforms into a perverted wife who feels more pleasure from her anus than her vagina. The crazy family situation where she can no longer return to normal sex life due to her anus.
