Iíve always gotten on well with my mateís wife, Cassandra. They married when she was very young and very shy. He is the same age as me, thirty-seven. She is a lot younger, ten years to be exact. Over the years, she came out of her shell more and more and began telling me how she didnít fancy her husband anymore. She said that they didnít have sex anymore. I knew this was true as my mate had been telling me the same thing. We all met regularly on weekends for a drink. She and I often had heart-to-heart talks. It was during one of these that I told her I would be willing to fill in for my mate in the bedroom if she wished. She just gave an embarrassed giggle, and there was nothing more said. Then one night, we were chatting over our computers. My mate had just started a new driving job and was away for a few nights. Anyway, the conversation turned to sex again, as it normally always did, and she asked me about that night I said I would fill in for my mate. She asked if I had really meant it. I said yes, of course I did, and that I could be around in half an hour if she wanted me to. There was a slight pause before she replied. I was beginning to think I had over stepped the mark when she finally replied okay. So, I headed out for her place with a few beers in hand. When I arrived, it was a bit awkward at first. But then she took me by the hand and led me upstairs to their bedroom. We had sex all night and into the next morning. We have only done this once more since then as I have lost interest. I am the sort of guy who loves the challenge, but once Iíve had my way, it is not as exciting anymore. Iíve now turned my attention to my wifeís sister. So, hopefully, that story will follow soon.