I've had many real life experiences. The following was my first.
My first wife and I started by swapping spouses with another couple. This was back in the 1970's when swapping was a fad in the United States. It almost seemed innocent, in that it seemed to provide some variety in sex without the risk that an affair would have.
We were socializing with another couple, who gradually let us know they were swingers. At first my wife was "I could never do that." But the husband spent a lot of time talking to her, and eventually she came to me and said that she wanted to switch. I was shocked that my innocent young wife wanted to be fucked by another man; but his wife was pretty hot, so I let my cock do my thinking. But what I didn't think about was how arousing it was to get back together with my wife after she had been fucked and found her cunt flowing with his cum. Some how it didn't occur to me that he would cum inside her, and when I realized he had, my head about exploded. This was back in the 70s when we were totally ignorant of STDs, and we were fucking bareback and sharing sexual fluids. My wife in particular loved for me to eat her freshly fucked pussy, and she would give me a hand job on my slimy cock to get me hard so I could fuck her. By the end of the evening she would have the cum of two men inside her and the pussy juice of the other woman from my cock.
I must admit that at first, my primary interest was in getting some new pussy, and I didn't focus on my wife getting fucked by another man. However, it did stimulate our sex life between my wife and I. We were continually thinking, and talking, about sex, either between us or with the other couple. I discovered that my previously-innocent wife enjoyed sex for sex's sake, without any feelings of guilt. But I think my wife came to believe that if two cocks were good, three cocks would be better.
She was working in a job where she and a male co-worker were alone in the office in the afternoons. Soon, he was fucking her before they each went home to their respective spouses. At first, she didn't tell me that she had added to her sexual partners. Once, I had gotten home before her. When she came in, she immediately wanted me to go down on her. She got me to eat her out on the front stairs inside the front door. What I didn't know was that she had just come from being fucked bareback by her co-worker. I did notice that she was particularly juicy, but I didn't notice any different taste. She put her hands on the back of my head and really pushed my face into her cunt, coating my face with the mixture of her lover's cum with her juices, and I licked and swallowed what was coming out of her. She had a weird kink when she got off on her husband eating her lover’s cum. After a bit, she pulled me up and started kissing me and licking my face, as I fucked her sloppy pussy.
Later she did tell me about getting the third cock on the side. I felt like I was hit in the stomach, but at the same time I found it exciting that my wife was such a sexual person that she could take on several men. That's when I started getting turned on by my wife with other men. The jealously and humiliation was more than offset by the excitement of imagining her getting fucked by other men; and by the emotional allure of knowing my wife was attractive to other men. It was only much later that she told me how she had fed me the creampie she had brought home from her lover.
Thanks for the story. Wish I could experience the same. Look forward to hearing of your other experiences.