True story involving my younger sister and I.
My younger sister was 14 and I was 16 at the time this happens. This memory sticks out in my mind vividly because it was such a great experience. She said she wanted to see me masturbate and naturally I agreed. We had seen each other masturbate before, so I couldn't say no. I loved masturbating in front of people at that time and I still do.
So we went to my room and I undressed and got on my bed naked. She was sitting on the edge of the bed contently watching my as I slowly stroked my cock. As she watched, I started getting harder and harder. I told her she needs to return the favor when I am done. Of course she agreed. It was taking me a little longer than usual to get off, so i suggested she do a sexy striptease for me. She was wearing just a long night shirt with cotton panties. She was hesitant at first, but when I told her it would help, she agreed.
She stood out in the middle of my bedroom floor and slowly started dancing. She slowly slipped out of her cotton panties continuing to hide everything from me. She turned around and slowly pulled her shirt off. She had such a little tight ass, I could feel the orgasm building, but I continued to hold off. She slowly turned around, keeping her shirt in front of her bush, but revealing her tits. That got me going a little bit more, but I knew I needed to hold off. She then took her shirt off and put it between her legs and rubbed it back and forth, getting her pussy juices all over it. After about 10 minutes of watching her dance naked around my room, I told her I was going to cum. She stopped dancing and got real close to my cock as it started erupting cum everywhere. It was one of the best orgasms I ever had.
After I cleaned up, I told her it was her turn. So she climbed on to my bed as I sat on the edge. She slowly started rubbing her fingers through her little mound of hair before slowly rubbing her fingers between her pussy lips. One finger went in and out very slowly. Naturally I started to get hard again. Then she asked since she had to do a striptease, that maybe I should do on for her. How could I say no, I was already hard. So I stood in the middle of my room, and started slowly stripping out of my clothes again. I could tell she was enjoying it because she inserted another finger and started going faster. Seeing her with two fingers in her tight pussy got me so horny that I started stroking again knowing full well I was going to cum again. I could tell she was getting close, so I started going faster to try and time our orgasms to happen at the same time.
As her hips started bucking on my bed, she started moaning and saying she was going to cum. Then she let out a huge moan and her whole body started to convulse and shake. Unfortunately I didn't time it right, I was a little behind, but I ended up shooting another load all over my floor and even managed to hit my sister on her leg.
It was such a great experience and a memory I use while masturbating before bed.