Mr. and Mrs. Hatano who came to the lower floor greet Mr. and Mrs. Otsuki who live on the upper floor. The moment I see them, the desires of Mr. and Mrs. Otsuki awaken. After confirming Yui's absence, Hibiki rushes to Yui's home and succeeds in sleeping Yui's husband. Hibiki enjoys SEX with her husband and Yui's husband, and one day he invites Hatano and his wife to a meal and reveals their relationship with Yui's husband. Yui who knew it finally had a relationship with Otsukio. The relationship between each other's couple is really ...