Good point, nice fantasy
I am sure it is happening but rarely ..
Why sure?
Because we had a wonderful experience similar to your thoughts...
We met a married couple who showed very interested in my wife. Our wives became close and shared time together, good moments as girls do... We stepped further and we used a nice opportunity to have a hot night in 3some with the other wife... It was very obvious she enjoyed watching people having sex but she was very hot and sensual as well...
After few months I was away and they invited my wife to enjoy a "jacuzzi evening" to their place... My wife was actually the gift for the husband, again being watched and encouraged by our friend wife...
Now swapping wives in threesomes was wonderful and relaxed but we needed a foursome as well.... We managed in finally arranging a weekend for all of us together...
We directly started by swapping wives and each "couple" enjoyed folding, kissing, whispering and touching like lovers do the same time watching the other couple...
My wife started fucking the other guy and his wife and I either layed beside them or stand nearby the bed watching continuously their love making... My hands over her tits, fingering her and kissing her, she was stroking me or giving me briefly blow jobs but mainly we were commenting their gestures and pleasure... "Look how much he is enjoying her pussy..." "Mmmm she is really having an orgasm now.." "wow he wants her ass ... Will she accept?" " Yes, do not worry she will take it in her ass, she is trained.." "wow, how nice...he is always asking me for anal sex, I started to love it.." "would you like us to try it too?" "No, let's watch them..."
It was sort of finding a voyeuristic man under the skin of a very sexy woman. We had sex as well, I was impossible to simply watch without any action, but we felt very close and happy before sex, after sex and long after that night due to the special mutual pleasure of watching
