When my wife and I were dating she had a friend that we would exchange pics with, we planned on doing a swap with her and her boyfriend but things never went through. She used to go out with her friend and the boyfriend and I always had a feeling something happened that she didn't tell me about. It wasn't until a year or so that she finally confessed she did have sex with her friend's boyfriend one night. It was after they went out to a club and her friend drank a bit too much and ended up passing out in the back seat on the way home. He ended up dropping my wife and her friend off at the friends house as my wife was exiting the front seat he ended up stopping her and pulled her towards him kissing her. Well apparently she enjoyed it because they ended up having sex in the car. At first when I heard it was a mixture of emotions, on some level I already knew but was still mad and jealous but at the same time very aroused at the thought. I would ask her for more details from time to time and we would always have some very hot sex after. I guess that's what got me into wanting to see her with another man and our current fantasies of watching her enjoy different cocks.