Sometimes, I just have to do something really dirty to get myself off.
I've known I have bi tendencies for a couple of years. I haven't done anything about it (yet) but I get really horny looking at other girls.
On the train home from college today a group of girls were sitting on the seats opposite me. One of them is in my year and has a reputation as being a bit of a slut. As she was talking and laughing she was squirming around in her seat and I could see up her skirt. I got very horny because her knickers were obviously wet, if you know what I mean. I am sure she felt horny too. I couldn't get the image of the wetness out of my mind. I was desperate to touch her and to smell her and to lick her. I became really fixed on what she would smell like.
Anyway, I kind of got it into my head that she might have wet herself a little, and for some reason, this really got me off. My clit was throbbing and I kept crossing my legs and squeezing. When I am horny enough, that can make me cum, but I wanted to do something really bad. I made sure I was sitting on the seat with my own skirt out of the way and I made myself let a little pee go into my knickers. All the time I squeezed and relaxed. Suddenly I cummed hard and really wet myself at the same time. All the time I stared up her skirt and I tell you, if she had wanted me there and then I would have had sex with her with everyone looking. I know I moaned because suddenly the conversation stopped, everyone looked at me and then burst out laughing. One girl cheered and clapped. The girl I was with said 'Lisa, did you just cum?' I nodded and she said 'Way to go girl!'
Well, I got home, stripped naked and jilled myself silly. I got to do more knicker wetting though. That is something I could REALLY get into in a big way.