I caught my wife fucking her brother's best friend. This happened about ten years ago when we were in college. We had been dating for about a year at the time and I decided to surprise her and visit her at her house one summer night while her parents were away on vacation. I got to her house after dark and noticed the light was on in the backyard. As I approached I could hear the hot tub running and was hoping to catch her nude in the hot tub which she did often when her parent's went away. My wife was butt naked, however she was not alone. Her brother's friend was also naked sitting on the edge of the hot tub with my wife bouncing up and down on his large and very thick dick. I was immediately turned on and decided to watch them fuck. My wife at the time was 21 around 5 foot 3 115 pounds with a smoking hot ass and her brother's friend was a very large, muscular black kid who played on the HS football team. My wife rode him for about 5 more minutes before he picked her up and bent her over. He pounded her pussy for a good 15 minutes straight like a jackhammer. He smacked her ass and pulled her hair which she loved. She must have cum at least 4 times from what I could tell and told him how much she loved his big dick inside of her. I have never heard her moan so loud to this date. When he was ready to cum, he made her get on her knees and swallow his load. I am sure they hooked up again, but I never mentioned it to my wife. To this day I hope I catch her doing it again.