Both me and wife are IT professionals and we were living a normal married life. We have two beautiful kids.My wife has one younger sister. Her name wa... Rupa. By the time I got married to my wife younger one has just joined college and lived with my in-laws. Rupa had a sexy figure and had fair skin.To begin the story even though I love my beautiful wife and kids. I always feel attracted to Rupa as she was very hot and friendly to me and she used to be very happy when we used to visit my in-laws.. I wasn’t going to last long, so I wrapped her panties over the top of my cock and pumped even harder. After about three strokes my cum started to burst and it filled the liner of her panties and started to spill out through the lace and onto my fingers. I don’t know if I’d ever cum that hard before. It was simply amazing! I tried to use her panties to clean up as much cum as possible. I wrapped them in toilet paper so as to not stain my pocket and shoved them inside. As I got back to my office,. I told her about me having sex every night with Mary for the next two years.The Principle thought it over and said, “I’ve got a better idea. You can have sex with both of them during second period right here in my office on school days, from now until the end of school. What do you girls say to that?”Mary was getting her promise cut by two-thirds so she liked it just fine. My sister objected to it because I was her brother. The principle asked to see my sister’s notes. She looked them over and. She felt someone between her legs and then a cock was thrust inside her. It was not unpleasant, she had been excited enough that her body was receptive, but still so quick it was not pleasurable either. It began moving gently.The hand pressed her head, while she heard, “Is that how you would take me Frank? Slow and hard.”“Fuck yes.” For the first time she heard what the male voice was saying.Her tongue circled the clitoris, another thrust, then another. Now her tongue felt that notch, the place.