Shimpei had the chance to visit his aunt's house. That evening, his aunt's younger sister and her husband were also there, and they happily chatted over drinks. The couple had a habit of wanting to have sex whenever they visited someone's home, and that night they slipped away to another room to begin. Shimpei secretly watched them while masturbating alone. When his aunt discovered what he was doing, she confronted him, saying, "You were watching me masturbate, weren't you?" Caught off guard by her words, Shimpei felt flustered yet increasingly aroused.