A couple returned to the wife's parents' home. That night, while her son-in-law was taking a bath, his mother-in-law Yuu brought him shampoo and started washing his back. Noticing something in her son-in-law's bulging crotch, Yuu began rubbing his erect penis. Unable to hold back any longer, he ejaculated. Yuu told him to keep it a secret from her daughter and gently kissed him. However, instead of calming down, her son-in-law's excitement only grew, leading him to sneak into Yuu's room while she was sleeping. From then on, the son-in-law and Yuu began satisfying each other's desires in secret, eventually getting caught by his wife. Half a year later, when he heard that his wife was going on a trip with friends, the first face that came to mind was his mother-in-law's. Before he knew it, he had sent her an email. A few hours after his wife left for her trip, the doorbell rang, and there stood Yuu, looking both embarrassed and happy…
