I was visiting my wife's parents' house. I wanted my mother-in-law and my wife to forget about housework and relax, so we went on a hot spring trip together. But I also had another purpose. I have a strong libido, and since I came back home, I haven't had sex in three days and haven't been able to sleep. I was excited to do it tonight, alone in the room, but my wife fell asleep early and I was spending the night in frustration when I happened to see my mother-in-law undressing.