Hi, my name is Eric, I'm 18 years old. I live in the country with my mom, my step dad Jeff and my 19 year old stepsister, Jessica. We moved here 12 years ago, when mom and Jeff got married. Our house is very isolated from the neighbours and from the road, and as far as I can remember; the whole family has been hanging around the house and swimming nude in our pool. It is more practical to be nude all the time anyways, since we spend so much time in the pool (being nude allows you to dry in seconds).
I guess nobody cared when Jessica and I were toddlers. But when Jessica turned 10 or 11 and her first pubic hair appeared, our parents decided to make us wear swimsuits when we are both at home. If one of us is not there, it's ok for the other to swim naked and to be nude around the house. Mom and Jeff are naked most of the time, this is somewhat frustrating. Approximately one year ago, on a hot day after school, I was alone at home and was swimming when Jessica showed up, naked, on the deck. She didn't know I was there. When my stepsister saw that I was in the pool, she clumsily tried to cover herself. It had been maybe 4 or 5 years since we had seen each other nude (our parents prevented that from happening).
I told her she should not worry about being nude since I already had seen her and that I was naked too. I was by the edge of the pool so she couldn't see all of me and she insisted that I proved to her that I was nude. I turned my back to her and moved away from the edge. After seeing that I was telling the truth about being nude, she said ''OK'' and jumped in the pool. The first few minutes were awkward but soon we started wrestling together and dunking one another like we always do, except this time we were both naked. With our naked bodies rubbing up against the other, my penis got harder than it had ever been. Through the wrestling I unavoidably touched my stepsister with my penis a few times and she noticed right away that I had an erection. She laughed at first and asked me if she was the cause of such an erection, she was intrigued by the swelling of my dick. She lightly squeezed my penis with her hand and said she was surprised that it could get so hard; then, she asked me how it felt when it got to that size. I told her that it felt great. I touched and grabbed her breasts. They were also much firmer than I had expected, her nipples were especially hard. We stopped wrestling after that.
We swam for a little while but my dick stayed hard the entire time I was in the pool. I got out of the water with my hard penis sticking out in front of me and sat there to dry, Jessica couldn't help but stare. I went to my room to dress, closed the door and started jacking off. Since we had been nude together most of the afternoon, Jessica didn't bother knocking and walked into my room and caught me in the act. I was very embarrassed she had seen that. Jessica apologized for barging in and asked me a few questions about what she'd just seen. It was very embarrassing but I gave her honest answers. She said she would like to watch me masturbate. I was a little bit shy about letting her watch but the thought turned me on too much for me to say no, so I resumed stroking my penis.