My wife, Kate and I were at a pub in Belfast, Watching a blues band, when some of our friends turned up and asked us to come with them to a party at Andy's flat. When the pub shut, we all made our way to the party, which was in full swing. I soon got chatting to some old friends and kate was talking to Les in the kitchen. After while I went back to the kitchen, but Kate had gone, so I had a look elsewhere. I took it for granted that she had gone downstairs. As I passed the loo, I heard voices inside and recognised them as Kate and Les. I tried the door, but it was locked. There was a space at the bottom of the door, where the step was missing, so I got down and looked underneath the door, as best as I could. Les was lying on the floor and kate was wanking his cock, while she sucked and licked his knob. I got up and knocked the door, but there was no answer. I knocked again, but still no reply. Some other people were coming upstairs and I didn't want to draw any attention, so I went downstairs. A minute or so later, Kate came out, followed by Les. I confronted her when she came downstairs and at first, she denied it, but when I told her what I had seen, she came clean and told me that she just couldn't help herself. She said that she had got the hots for Les and was going to screw him once, whether I liked it or not. I found myself being turned on by what was happening and eventually agreed. I said that she could take Les home and that I would stay at the party for an hour and that when I got home, I didn't want to find Les there. I had always told Kate that I didn't mind her having a one night stand, as long as she kept it discrete, but this party was not the place for a discrete fuck. I saw her leave with Les about five minutes later. When I got home, Kate was sitting on the chair, in the nude. She had just showered and was drying her hair. "Are you going to tell me about it" I asked her. She nodded,yes. She told me that she had finished giving Les his blow job as he drove her home and he had come in her mouth and once in the house, she had let him fuck her from behind and shoot his spunk inside her. I was so turned on by this, that I dragged her into the bedroom and fucked her for hours, until we eventually fell asleep. The next morning, when the booze had worn off, we talked about the night before and decided not to make a habit of it, too often