Tomoka is married and lives with her husband and his father. Her sex life with her husband was calm and bland, but she was reasonably satisfied. Over time, however, their intimacy grew less frequent until it eventually stopped altogether. Tomoka has a strong libido, far exceeding her husband's stamina, and she began moaning loudly during sex, unable to hold back. With no other outlet, she started filling her solitary moments with masturbation. Her father-in-law secretly observed her, keeping a detailed diary of her habits for his own pleasure. At some point, Tomoka’s clothing began to change—she started dressing more provocatively, often appearing nearly topless or bottomless. At first, he assumed this was related to her relationship with his son, but upon rereading his diary, he realized she had adopted this style only after her sexual activity with his son had completely ceased. One day, her husband went to work and her father-in-law left for an errand. Alone at home, Tomoka indulged in self-pleasure, only to be discovered when her father-in-law returned unexpectedly. He froze, staring in shock at the scene—yet soon became aroused by her desperate moans and helpless form, ultimately giving in and taking her. His experienced, relentless foreplay overwhelmed her, especially his intense, prolonged cunnilingus that made her climax repeatedly. His cock was larger and harder than her husband’s, and the moment he penetrated her, she was driven to instant ecstasy. A few days later, while the family was out, Tomoka wandered alone, pulled her father-in-law’s underwear from the laundry basket, and quietly inhaled its scent. As memories flooded back, she slid her fingers between her legs—her own panties already soaked with arousal.