I have been seeing a couple, Mark and Mary, for about 10 years now. I met Mary at work. She was about my age (late thirties then), very flirty and very sexy with large breasts. One Christmas I had a “Christmas kiss” with her and told her that I fancied her. I said, half joking, that if ever she wanted to go to bed with me she just had to say. After Christmas, to my huge surprise she said she would like me to fuck her. As we were (and are) both married we arranged to meet in her house when her husband was out. We met and I gave her a good fucking but it was quite quick as I was excited (!!) and I didn’t want her husband to catch us. The next day at work I got a chance to chat to her. When chatting she asked me to tell her any fantasy I had. I told her that I’d love to fuck a woman in front of her husband. With a twinkle in her eye she said that she might be able to arrange it! I was gob smacked! It turned out that Mark and Mary had been fantasising about her being fucked by another bloke. A few days later I went to their house and met Mark for the first time. He was quite happy for me to fuck Mary, in fact he didn’t want to watch but he wanted me to cum inside her so she was all wet for him. I was happy to oblige. Mary is a fantastic woman who loves sex. She made sure I came deep inside her. I went to their house on a regular basis. As time went on Mark used to come into the room to watch me slide my cock in his wife but he never took part and he never got his cock out in front of me. I questioned Mary about this. It turned out that my cock is much bigger than Mark’s and Mark didn’t want me to see this. I’ve always known that I have a bigger than average cock but it never been any big deal. However, I was quite happy to get my cock out in front of him. I liked him to watch me slide into his wife and I always made sure he had a good view of my cock. We had many memorable sessions. I remember that I called at their house unexpectedly early one evening. Mark suggested that I fuck Mary now and then come back later for a more leisurely shag. So Mary sat on my cock in front of Mark and I quickly came inside her. When I called back a couple of hours later they were waiting for me. Mark said that he’d fucked her twice since I had been and that it was my turn to get some of his cum round my cock. I got my cock out; Mary guided it in to her dripping fanny. She was soaking. I then added my cum to his and I know that when I left, Mark was going to fuck Mary yet again. As the years have passed we have had some great sex with oral, toys, video and the like and importantly, we have remained friends. Recently Mark has been taking some tablets for a heart condition and these have reduced his sex drive. Because of this I have not seen them for some months. However, I bumped into Mary recently who said that as soon as Mark was off the tablets and felt like sex again she would call me to service her with my big cock.