In the bride's parents' house, it was customary for both sisters to visit their parents' house at the same time. It's that time of year again, and I'm going to bother you, but when I'm walking down the corridor, I see something bad when I see it. Sister-in-law's masturbation... Because of this, I have a secret that I can't tell my wife. I lost myself in the pleasure and excitement of the complex incest of my sister-in-law and brother-in-law, even though I had an immoral feeling.