My wife and I have been married over 20 years the wife has a well paid job for which she has to be assertive and coinfident which over the years has made her the same at home. In times of frustration she has been telling me my cock is not very thick and is not giving her the satisfaction that she needs, I have said that its probably about average size and tried to improve my performance but the pressure was making me perform worse I would cum to soon or couldn't get an erection at all. One night after I had failed to satisy her she said wanted to try sex with a man who had a larger cock to give her a real good fucking to get her the sex she craved. I asked her not to but but she was adamant and said I had had my chance and it was my own fault, she would prefer to this with my knowledge rather than cheat behind my back. So we went on a few web sites looking for guys who offered to give married women great sex and claimed to be well endowed and a heavy cummer,she selected a guy who had a photo showing his cock which she took delight in saying made mine look like boys. I was given no choice and a date was arranged for him to come round to the house and he did not mind husbands watching, my wife bought special sexy black stockings,suspenders, tiny panties, matching bra and heals,when ready she looked stunning. After he arrived and introductions done it was agreed i would sit in a chair in the corner of the bedroom and take no part except for some photographs, he then started to kiss and caress her while taking off her dress to revel her beautiful body encased in the sexy lingerie he complimented her on her looks and sexiness. She then undressed him to his boxers and i could see the shape of his semi erect penis and it did look big , she sank to her knees and savouring the moment pulled his boxers down and his huge penis sprang out in her face at which she gasped, I was amazed at its size and new i could not match it. She then took it in her hand and wanked it and as she took it in her mouth, i was mesmerised and jealous and getting an erection of my own, as she gave him a fantastic blow job , his breathing increased and suddenly ejaculated in her mouth and there was so much spunk it ran down the sides of her mouth and chin at this i shot my cum in my boxers, she was loving it!. He then spent a long time pleasuring her with his tongue and hands until she orgasmed , he had recoverd his erection with help from the wifes hands and mouth,at this point he turned her over and entered her from behind she was loving being filled by his erection which made my efforts seem inadequate at this time he increased his rytham and she met his thrusts and before long he shot his heavy load over back, she called me over and humiliatingly said as you so enjoyed watching and wanking, asked me to clean her back of his cum. They spent the rest of the night having sex in serveral positions he must have cum least 3 more times over the evening and my wife was very satisfied, after he had left we discussed what had happened and i had to agree with her that i was unable to satify her like he had and was forced to agree to her having more regular sex sessions. So i watch her getting great sex from guys and sometimes i can have a good erection of my own and have sex with her after the man has left. I feel totaly cuckolded.