Sister leads wife astray
A few years ago, my wife's younger sister went through a rough divorce and my wife started spending a lot of time with her. They began going to nightclubs and before long she was staying out half the night. I kept asking her about her activities and she would only say, "I'm not doing anything wrong." I usually slept through her arrival home, but on one occasion heard her showering in the middle of the night. Next time she went out I made sure that I was awake, but pretended to be asleep when she came home. I was hoping to hear her conversation on the phone with her sister. Instead, I saw her toss her panties in the washing hamper and go in the bathroom to shower. I eased out of bed and retrieved her panties. They were soaked with sperm. I was numb with shock and disbelief, but carefully replaced the panties and crawled back into bed. I found myself imagining her banging some strange man and became highly aroused but afraid at the same time. When she came to bed, I kissed her and pulled her on top of me and I fucked her hard, she was extremely aroused.
Afterwards I told her that I knew what was happening and she broke down in tears and admitted everything, saying she was deeply sorry and begged for my forgiveness, she promised that she would quit running around with her sister. Eventually I got out of her that she had been with about five different men. I would get raging erections thinking about her going down on one of these strangers man or screwing them.
I finally admitted to her that I didn't know why, but her screwing these men was such a turn on for me. I told her if she enjoyed it and would not loose affection for me she could continue her activities, but on condition that she must describe to me every detail. She readily agreed and this has now become our favourite pastime and our sex life has become incredible.