My wife's college friend came to visit us this last weekend. Her and her husband showed up on Friday and stayed until Sunday. Friday night they were tired and decided to retire early. My wife and I were sitting out back on the deck drinking wine. It had been a couple hours since they retired for the evening and I was feeling quite frisky. I convinced my wife to strip and show me her tits, then her pussy. She pulled down my pants and was in the middle of giving me a blowjob when I looked up and saw her friends husband standing in the doorway watching us. My wife's ass was facing the door so he had a clear view of my wife's pussy from behind. I never said anything and just let my wife continue giving me a blowjob. She finished blowing me and got on top sliding her pussy down on my cock. I made sure to pull her forward and lift her ass cheeks apart so her friends husband could get a good look at my cock going in and out of my wife's pussy. From time to time I would look around my wife to make sure he was still there. I noticed that he had his cock out stroking it at one point. Shortly before we finished i looked again but he was gone. I hope he had a good show.