We grew up during the time period when conversion vans were the rage they were everywhere. We would go on van rallies which basically consisted of all day all night party and normally a fair amount of nudity due to wet T shirt contests and what not. It was not uncommon for things to get out of hand quit fast which lead to plenty of sexual adventures. This particular afternoon my bride to be was in rare form feeling pretty good about her surroundings so she became more care free than normal. It just so happened that her ex sister in law was there also and I'm not sure if she decided to give her ex husband something to hear or what but she decided we should go skinny dipping with her ex sister in law. So here we are broad daylight people all over the place and we strip off our clothes and go into the river. I figured she had her fun and would get out and get dressed again. Much to my surprise she decided it was time to fuck. So here we are in the river her ex sister in law about 10 feet away and she has her legs wrapped around my waist and my cock buried in her pussy. I figured this was way further than I expected to get in this situation until she whispered in my ear " fuck me" I slowly started lifting her up and down on my cock while the shoreline is filling up with people. She leaned to my ear again and said I told you to "fuck me" I said what do you think I'm doing? The next thing you know she screams at the top of her lungs that she wants to be fucked hard. Now any attention we didn't have we had it now as I lifted her up and down as fast as I could with her gorgeous tits on full display and her pussy getting railed. Her ex sister in law was memorized by what was happening and just stood and watched us fuck. The crowd on the shoreline was cheering as we put on quite the show. Needless to say we had a difficult time the rest of the weekend as every guy and gal in the place thought we were both up for grabs. Who knows if she got fucked by others that weekend because several women were pulling me into tents or trying to pull my shorts down. I know I had my hands full but neither of us ever said a word about what happened when we weren't together.