I was getting the seven year itch and was actively looking to cheat on my wife. Then I heard from a mate of a group that engaged in sex parties. My thoughts ran to taking my wife and if she engaged with it another man then it wouldn't be cheating for me to fuck another woman. I told Mandy about there being a party and did she want to go. She knew several of the people that would be there and quickly said yes. I was chuffed. First part of the plan ticked off. Now all I needed was for someone to fuck my wife and I would be on a home run and be able to fuck someone else's wife. Mandy wore the shortest sexiest dress an looked a million dollars. I almost didn't want to go through with it seeing her look so sexy. At the party as people began to mingle, the men were like bees around the honey pot with my wife, and Mandy was loving it. I was just waiting for Mandy to go to one of the bedrooms with one of the men before moving in on one of the many sexy ladies. To my surprise I didn't have to wait too long as she was led away and I watched as they went into a bedroom. I had singled out a woman I fancied and went to chat her up. I was a little upset that she wasn't into me and soon found an excuse to get away from me. I noticed that a lot of the people had now seemed to couple up and there was just a few women and men on their own. After a second rejection I was getting desperate and made a play for one of the few now remaining. Was I relieved that I got lucky. Whilst not the best looking or the sexiest she was ok so I escorted her, looking for a spare bedroom. There wasn't one so in the end we ended up in the garden and fucked on a bench. She was ok but it was a little uncomfortable. Afterwards we returned to the house and got fresh drinks. I noticed that there was now more women than men hanging around. The woman I had been with wandered away and I wondered if I was lucky enough to be able to bed another of the women. After several conversations with some of the women I eventually found another that was willing to fuck with me and we went off upstairs. There seemed a bit of a queue for the bathroom, but an even longer one for one of the bedrooms. It wasn't the room Mandy had gone into so I wasn't interested in what the queue was all about. I found us a room and we got down to business. We fucked but it was like pounding away at a bag of spuds. There was no movement or reaction from the woman and after a very mechanical fuck. she left me and returned to the lounge. After some recovery time I decided to go for another drink. On my way along the landing I asked what they were all waiting for. I was told there was the hottest woman ever and she was working her way through the queue. Again as it wasn't the room Mandy had gone into I thought no more about it. I declined the offer to join the queue and went down stairs. I was stood with my fresh drink when the man that Mandy had originally gone with came up to me and told me just how hot my wife was and what a good fuck she was. I was quite proud knowing someone thought my wife was hot. Then he said something that shook the hell out of me. It was when he said that all the others also thought so. The words, all the others, rattled in my head. I asked what he meant and he said that the five or six guys that had already had her thought so as well, and those in the queue obviously thought that she was worth a try. Now I was worried. It was Mandy that was in that room with god know how many men and what she was allowing them to do to her. I was up the stairs in what felt like two bounds and at the head of the queue I turned the men away saying it was over. The men pushed back but I held my ground and forced them away. Then I was in the room. There was my Mandy an hands and knees sucking a man's cock and being fucked by another from behind. There were two others in the room stroking their cocks. Mandy looked drenched in sweat and cum on her and it seemed just seconds when I saw her take another load in her mouth. one of the men wanking went to take his place but I stopped him and told him it was over. Mandy watch me usher the man that had just come in her mouth and the other two out of the room. I was too late to stop the man fucking Mandy before he dumped his load into Mandy's pussy. Mandy collapsed onto the bed exhausted. I asked where her clothes were and was told that they were still in the first room. I left Mandy there to dash for her clothes and in those few moments on my return another man was plowing Mandy's pussy. Mandy had a pleading sort of look on her face that said she wanted this. I waited until he came in her. Then I dressed Mandy and helped her down stairs. There was a lot of men cheering and clapping as I helped her down and out the door. Back home she want straight to bed still covered in cum and sweat, and I was left wondering what the hell I had done. The next day I asked Mandy what the hell was that all about fucking all and sundry as well as sucking them off. She laughed and told me it was my own fault. I must have looked confused. She informed me that she knew that it was a sex party as she had been told by several of the people she knew at the party, in fact well in advanced of the party. She said she knew what I wanted was to fuck other women and she decided to make me suffer for my wants. Then she added that she had asked that the women rejected me so I didn't get fucked while she did. The message hadn't quite gone to all the women fortunately for me. Mandy continued that she hadn't intended to go quite that far with the men, but she discovered how much she loved it and couldn't help but allow the men to use her as they liked. She continued that whether or not I liked it she intended to do it again. I pleaded with her not to, but three weeks later she was preparing to go out and told me that with or without me she was going to another sex party. I didn't want to but I went with her, and whilst I enjoyed some time with Denise, afterwards I again witnessed Mandy with quite a few men. I couldn't take it and had to leave the party and go home on my own. When Mandy finally came home looking as if she had fucked the 5,000 I told her that I couldn't do this anymore. "Good," she said, "I only did it to teach you a lesson. From now on if you want other women it will only be in straight swaps." I agreed with her. It was a month or more before our first swap, and while I enjoyed the swap and the partner I had, I couldn't get the vision of Mandy with all those men out of my head. It was well over a year before our next swing. I enjoyed that one much more than the previous one as the visions of Mandy were no longer fresh in my mind. After that about every three months we would find a new couple to swap with. I got to really enjoy the sessions. Mandy did say a couple of times that she would like to try two men again, but she never pushed it and I told her that I don't think I could accept that. We came to the understanding that straight swaps was our only option if we wanted to stay together. That was fourteen years back now and up until the pandemic we were still very active. We are now looking forward to finding our next couple to swap with.