Kaoru always treated her son with kindness. Even when her husband objected, she gave him spending money after he announced he was going to a mixer. That night, the son came home late and quietly slid open the shoji door to peek into the bedroom. There, he saw his parents secretly having sex. A few days later, remembering the sight of his mother, the son began masturbating. Unaware, Kaoru entered the room and trembled upon seeing her son's crotch. One day, Kaoru was masturbating while thinking about her son's cock—when suddenly, he appeared, and she panicked, trying to hide what she was doing…