When I was 15 I asked a girl I liked out on Valentine's Day. It was so romantic and all that other mushy love crap. We went out for just under a year and had many sexual experiences. She was pretty much my first time for everything and we had a great time. We never had sex, but we did masterbate together, each other, for each other, etc. So that's enough history let me tell you about one Saturday in her car.
Sometimes on the way home from movies I would still be so horny from playing in the movie that I would pull down my pants to shock her while she drove (she was 16, I was still 15). One time I even got naked. So one Saturday, I was horny while we were driving around so I suggested that we go to this old shopping center parking lot and park. We'd parked here before and I masterbated for her, shooting cum across the car at her (I think it scared her) and this time I wanted us both to have fun. She was nervous about being seen or caught but I assured her no one would bother us. So I pulled down my pants and boxers showing her my dick and she looked at it nervously. I could tell she didn't want to do anything here and was too scared. So I suggested what we leave but she said, 'No, no, here goes,' and pulled her pants and panties down enough so that I could get access but not really see anything. I reached my hand over and began to finger her and she reached over and began to jack me off. Then we both were stunned that we were actually having a mutual. We watched the shoppers and cars driving by and continued for a few minutes. When I approached my orgasm I, not realizing it, stopped fingering her and started moaning. Then it started to cum. She immediately took her hand back (afraid of cum I guess) and handed me a towel to clean up with. I apologized for stopping and offered to finish her off and she said, 'It's ok. I already came twice.'
It was so great and we had many more sexual adventures. Next time I'll tell you about being in her room while her parents and sister were home!