I'm open and honest with my wife, I think it takes a very trusting relationship to do something like this...to know its purely physical and to fulfill a fantasy. My wife knows all about my gear, the risks involved in obtaining it etc. - she's even pin'd me in places I can't reach - rear delts and back with IGF-1; I tell her everything.
One of her fantasies is to be with another woman, but she does t know how to make that happen. Fast foreword to this scenario. Wife and I go to said couples house for dinner and drinks under the premiss that his misses will make an advance on my wife and we watch, don't participate. See where it goes from there. I dunno still up in the air but I could make this happen...you know, for the good of the misses and all.