The older sister offered her body for her beloved husband

It's been a few years since I married my younger husband, Nobuo. His wife, Reiko, feels happy that she is loved, but she is lonely because she doesn't have much time. One day, Reiko, who has distrustful of Nobuo, who is different from usual, forcefully asks her questions... He was drunk and missed his sex and was caught in a beautiful woman. Although she was shocked, as her older sister's wife, Reiko heads to the negotiating venue in place of Nobuo. However, the men could not just have money and an apology...