For one summer, my sister and I seemed to connect sexually, we were both going through puberty at the same time.
When I was growing up, I was always sexual. At the age of six or seven I would open my pants and show my penis to my family members and stuff. It was cute, because I was a child. However as I grew up that sexuality hightened.
I have a younger sister, Chris, two years younger in fact. I was 13 and she was 11. They say girls mature faster than guys, so we were both a rage of hormones. Somehow the topic turned to sex one day. We didn't know much about it besides the usual 'I'll show you mine if you show me yours.' I played with myself, but hadn't cum yet.
One day I managed to come across my fathers porno videos. I managed to get my sister into my bedroom, she layed on my bed and myself on the floor. I put the video in and the movie began. There it was, the first scene was an orgy and I was hard as a rock. As my sister layed on my bed, I pulled my pants down and started stroking in front of her (I didn't even think about it, I just did it). I looked up and she was still clothed, but had her hand between her legs squeezing her thighs together. I kept stroking my member and between the video and watching my sister I came for the very first time. She looked on and I will never forget seeing cum dripping out of my penis for one of the first times. I still remember exactly how it looked, it kind of raised out of my piss slit. I looked up at my sister, who was smiling, I took a paper towel and wiped it off.
That was about it. We had a few repeats, she let me do some dry grinding on her. I eventually saw her pussy (my first ever!) which was hairless but she never let me see her chest (I did peek years later, and I must admit she has the most lovely 36c's) and a nice trimmed bush. Most of my friends tell me how much they want my sister, and I pretend to be pissed, but secretly I love it.
So, sis if your reading this, I cherish that summer, don't be afraid to show the world what you got! (and me too!)