Having been a "swinger" for a number of years, over 20 in fact.. and enjoyed some rather erotic liaisons as a stunt cock with a local mature married couple for about 10 years, it came as a complete surprise one day when as the lady of the house was riding my cock hard, she whispered quietly into my ear that she really wanted to watch her husband suck my cock....words which when whispered into my ear evoked an instant orgasm on my part flooding her pussy with my semen and her continued hard riding until I felt her vaginal muscles contract as she too reached her own orgasm. Apparently for much of the time we had been having our threesum fun, the husband was fascinated by her enjoyment at sucking another guys cock while he was sitting at the end of their marital bed furiously wanking his rather thin but long cock as she was vigorously engaged in sucking or fucking my long and thick cock..... The subject was brought up again a few months later, during one of our 121 session without her husband present as he was working away, and I was summoned to come and service her needs as she was very horny.....The situation was that she was again astride my waist, my cock buried deep in her very wet pussy, her feet turned inwards under my thighs, she pushed her breasts together as they were quite ample and started to lick and pinch her nipples, while all the time maintaining her rhythm of sliding up and down my throbbing hard cock..... She gripped both of her hard nipples between the forefinger and thumb of both hands and squeezed, I cold also feel her vaginal wall muscles contract as well, gripping my cock as it slid in and out of her well lubricated hairless pussy..... You know, she said..... I have spoken at length to hubby about what I said to you a few months ago and he is keen to experience what it feels like to suck cock, to know how it feels, tastes and to feel a guy explode in his mouth as you have done with me over the years.....how do you feel about it? My answer was simple, to grip her sides, just about her pelvis, press my thumbs in slightly to her flesh and thrust upwards, her moan of consent was all the encouragement I needed to fuck her hard, deep and fast, and after a few frenetic minutes my cum was delivered to her shaven pussy..... As we lay in the post coital embrace, as was usual she told me of her plan...... one which she was itching to see fulfilled as soon as possible.......