Following a holiday in France some years back, a couple of similar interests to Jan and I kept in touch; We had spent several days together on a naturest beach at Port la Nouvelles, sunbathing in the nude, and on returning home met up for what we called naked chill-out evenngs. These were agreed as stricktly same-room sex meets, each keeping to our own partners. Jan was dead set on preserving our married fidelity and rejected any suggestion of swapping. Rob and Teresa were less specific but respected our arrangement, yet still enjoying watching Jan and I pleasuring ourselves on the duvet on their lounge floor. Then things changed; I had been spending longer than usual caressing, fondling, sucking and generally warming Jan up; she adjusted her position and opened her legs signalling her readiness to be penetrated, taking my cock easily until I was fully inside her welcoming cunt. The slow thrusting started, our bodies soon achieving that unison of rythym that usually led to a good fuck that satisfied us both. Then disaster: my cock started softening, unable to sustain it's ability to keep inside her. "Sorry my Peach....I've lost it....." The glazed look in her eyes told me she was well on the way to a good orgasm, and not up for a forgiving end to my innadequacy. As I lifted my sad body off hers, she moved round on the duvet offering herself to Rob. I vaguely remember Teresa telling Rob to "go for it"..... As I sat back in the armchair feeling pretty naff, Rob moved down and carried on where I had left off; lifting Jan's legs he rested his cock-head against her cunt lips, slowly massaged her breasts and belly before slowly easing into her....I vividly remember the sight of his rigid cock vanishing inside her, and her gasps of 'yes, yes....' as he started a very robust thrusting using all of his length, on occasions slipping right out of her before re-engaging. There was some good natural lubrication, too, as his thrusting was accompanied by some very liquid noises. Teresa joined in by playing with Rob's bum and balls, a factor that may have sped up his cumming; possibly remembering some unwritten agreement not to cum inside a partner, he withdrew his cock just as the first of several spurts of spunk shot over Jan's belly; amazingly, she reached down and pulled his still-ejaculating cock back inside her. Unbelievable, Rob, still hard, then carried on fucking her for another couple of minutes before finally softening and slipping out, a small token of his love-juice following. Then the bizarre: Teresa got down and started licking the spunk off Jan's belly, then the small residue still evident on Rob's wilting cock. After a few minutes recovering on the duvet, Jan eventually got up and joined me on the armchair, her face a mixture of pleasure and guilt. Clearly she had not thought through my reaction at the moment she offered her cunt to Rob, she being well on-heat. For me the embarrassment was losing my erection before I had finished the job. Honours even, a draw....we hugged, I told her it was ok, glad you enjoyed it. She said sorry several times after, but a few weeks on and we have come to terms with it and have finally agreed with Rob and Teresa that a swap would be fun, no hang-ups or inhibitions, and that creampies are quite acceptable. Our next get-together is in early November......mmmmm!