We were fairly newly married, about a year, when one of my wife's best friends from school got married. We returned to her hometown for the event and a couple of days after the wedding were invited to there new apartment. There was no furniture! Newly weds? Ehh? Just some cushions on the floor. We had a few drinks and the girls reminisced about their school days. I had noticed her friend glancing at me, but thought nothing of it, until their conversation got around to the guys that they had fooled around with at school. Her friend (Sylvia) by way of explanation reached out and slid her hand up my shorts and cupped it around my balls and rapidly stiffening cock just as she had done to some senior guy a couple of years before. Being naive, I just smiled and froze, (we were in our early twenties and I had only ever had sex or seen a girl naked once before my wife) but then slowly I noticed that her new husband and my wife were just laughing and he said, Yeah and then what did you do? Sylvia immediately replied...sucked him off there and then. Really! said my wife........dare you to show us! I literally couldn't believe it, my wife was a little drunk, we all were, but she was still very much aware of what she was saying. There I was being given the opportunity for a sexual encountered that I had only ever dreamed of. Sylvia didn't wait to be dared twice, she grabbed my shorts and pulled them down, underpants as well. My cock, no surprise was as stiff as a board, my face was bright red with embarrassmnet . I lay back and let her gobble me up like she had been wanting to for years, eyes closed , but I could hear my wife and Sylvia's hubby (Erik) giggling and egging her on. My eyes were rolling at the enormous pleasure, but still a little concerned as to how my wife would react as it suddenly went quiet, my fears were allayed as I opened my eyes and saw Sylvia's hubby had moved over and started to kiss her..passionately...his hand was swiftly inside her top massaging her ample tits (something Sylvia was lacking in) Of the many thoughts rushing through my head I decided that this had to go on, I put my own hand down Sylvia's t'shirt, she had no bra on and her nipples were erect and huge compared to the size of her tits. I knew that I could not hold back my orgasm for long as Sylvia's tongue and lips were thrusting all over my cock. As I let out an almighty gasp I exploded inside her mouth, it was one of those memorable orgasms that seemed to just go on and on. Sylvia kept on licking and sucking as I softened. As I looked around Erik was gleefully pumping my wife for all he was worth whilst holding onto a pair of magnificent tits that he did not otherwise have the chance to enjoy. My wife told me after that he had started by tit fucking her, but she was so intrigued by his long thin cock that she asked him to put it in her pussy. Meanwhile, I thought in for a penny....so I asked Sylvia if I could kiss her pussy, without a word she whipped off her clothes and sat legs wide apart on my face and as I got busy in the delight of a fresh and very moist pussy she continued to suck and lick my cock like she had never seen one before. As she gyrated on my face I could feel her starting to cum and her intensity on my cock lessened, until she suddenly sat bolt upright and screamed like a banshee with the most extreme pleasure.
By this time we were of course all naked and as the girls looked at each other they seemed to instinctively know that each wanted to swap back to their own hubby. Erik and I sat on our cushions as jointly instructed and our respective wives came and sat in front of us. We kissed and cuddled and as we were both getting stiff again, our wife's rode each of us in unison. Any guilt that I felt about being sucked and licking another woman melted away as my wife bounced and stared into my eyes. I thought, yeah, your tits are much better.
To this day I suspect it was a school girl fantasy of their's that they made come true on that very special night.