Me and Sophie have been married 18 years and have 2 children. Sophie is a very attractive, young looking and very sexy. Our sex life has been good and we have enjoyed trying different things throughout our years together. We have talked on many occasions about sex with others and I have always found the thought of Sophie and other men a real turn on. Sophie herself gets turned on we talk about her and what other men would like to do with her and we usually enjoy good sex afterwards. However, several months ago Sophie joined a gym in order to get in shape and to look after her size 12 figure. She really tooh to the gym and started going about 2 or 3 times a week. After a few weeks I noticed that she was going straight from work and sometimes staying there until late. My suspicion grew when i noticed her texting one evening and she stopped as I entered the room. After one session at the gym she came home looking flustered and said she had enjoyed a good workout. she always had a shower after the gym and on this occasion stated she was going straight to bed. I followed her up stairs and she was in the bathroom cleaning her teeth. I noticed that her discarded knickers were on the floor in the bedroom and they were a pair of her more sexy ones, not a pair I expected her to go to the gym in. This drew my attention and I went and picked them up. They were moist and they had white stains in them around the crutch. I realised that it must be spunk that has leaked from her and I knew it was not mine. Sophie came in the bedrom and caught me looking at them, she knew I knew. I said nothing and climbed into bed, Sophie also got in. I asked who had been fucking her, she replied nobody, I asked her again and she asked if I was angry. I wasn't angry but very aroused. Sophie opened her legs and asked me to look, her clit was slightly swollen and her vagina was wet and open. I could tell by looking that she had had another man inside her, there was also sperm in her pubis hair and a residue on her anus. I have never felt so turned on and I asked her if she wanted seconds. She did and I fucked her spunky hole until I came inside her.