One night and two days of 1 night and left alone by my wife's sister who suddenly came over

Shinya was left to be his wife because of a casual comment. I apologized desperately, but my wife was in a good mood. At a loss, my wife's sister, Keren, decided to take on the relationship between her and her husband. She is strangely close to her, perhaps because she is worried. Just being stared at her beautiful looks makes my heart pound. It can't continue like this. He takes a shower and tries to cool his head... but for some reason, Hueren also comes into the bathroom...