I have written another story before, but this one has nothing to do with the other, but here is the link anyway.
I have two sisters, one is fifteen and the other is eighteen. This story involves my younger sister.
My sister has filled out quite a bit in the last six months and she seems to be always trying to flirt with all my guy friends, so I am thinking that she is fairly horny.
I haven't had a girlfriend since school ended, so I have been left high and dry except for masturbating, but even that can get a bit boring to a 16-year-old guy that masturbates every day twice a day. Anyway I'll get on with my story.
It has been a hot summer in my town where it is not usually so hot. Nobody in my town even owns an air conditioner, table fans are all we have because we never really need much relief from the heat. This summer, since it was so hot, though my dad bought the family one of those soft side pools that go above ground, and are like three and a half or four foot deep. Needless to say, myself and my sisters spend lots of time in the pool. My sisters in skimpy bikinis and me in shorts.
One day about a week ago it was only me and my younger sister. I was really really horny that day and hadn't had a chance to masturbate in the past 48 hours because of lack of privacy, so in my state my hot sister really turned me on. I had a huge hard on in the pool and couldn't get rid of it. I ran inside because I had an idea. I cut out the netting from inside my swimsuit and went back to the pool The netting was like a restraint that made it look like I had no erection at all, but once I had cut it out nothing was left to the imagination. She didn't notice it, or at least I don't think she did when I got into the pool again. I started playing around with her and wrestling and splashing. There was some grabbing of her thighs involved and her ass and breasts and even very minimally on her pussy. I even grabbed her and gave her a bear hug from behind and my hard on was pushing against her ass. To my horror she said is that what I think it is? I paused thinking of what to say. I then said 'Yes' and begged her not to tell dad. She agreed but said that I would have to clean her room for a few weeks to make up for her not telling.
So a week went by and I was cleaning her room and I found when doing so a thong of her's that seemed very fresh. I stashed that in my pocket and continued to clean. Ten to fifteen minutes later my sister came into her room in a bikini. As it was still scorching hot outside I said I was just finishing up and I left the room. Later that night around midnight I retrieved the thong and started to rub it on my dick and masturbate with it. I then came into it and then put it in the laundry to erase the evidence.
The very next day I was looking for her to ask her something and found her standing up by the computer desk, but bent over typing on the keyboard on a instant messenger. I immediately got hard and thought of the pool incident. I got up the courage to actually take my dick out and I lightly rubbed it against her ass. I don't think she felt it or at least she pretended not to feel anything at that point, but she noticed my presence and I began to talk to her as normally as I could.
I started to get close to coming and my cock began to shake and jump with excitement and then she noticed it, but at that point I was too far gone and started to ejaculate, even getting some cum on her. I was horrified that this time she was going to tell dad for sure and I would be dead!!
If you would like to hear the rest of what happened please request with feedback, thanks!