Hey, I'd just like to say that this site is great! I check it for new stories every day and they always make me extremely horny.
This story happened a few months ago at school. It was during the last 15 minutes or so of lunch. I had read of people who masturbated in bathroom stalls, or even in urinals and had wanted to try it, but always chickened out. I was getting horny just thinking about it, in addition to seeing all these hot girls walking around, so I decided to just go on with it. I had to do it; otherwise I probably would've died. I walked right in to an upstairs bathroom and into the furthest stall.
I was shaking, but my dick just kept getting harder and harder. I put down my backpack and unzipped, taking it out to get to work. The risk factor was a big turn on and the door opened a few times, but luckily no one used the stalls. I tried to hide my moans and heavy breathing, so as to conceal what I was doing. Every time someone came in I would go slower to hide the sound.
Then someone came in to use the urinal and I looked out the crack in the door. I heard moans and grunts, so immediately knew what he was doing. I'm not gay, but I was turned on by that sight and it caused me to stroke faster.
I felt the familiar tingling sensation and aimed toward the toilet bowl, but instead my cum went flying all over the floor. The orgasm was one of the strongest I ever experienced. It was probably because I was so excited and scared, but also very turned on by the risk and the fact I was masturbating in a school bathroom.
I walked out calmly, washed my hands and left. When the guy at the urinal heard my stall door open, he started to shake and his face turned paled. I guess he didn't know I was in the stall, just a few steps away from him. I still wonder if he ever suspected that maybe I was masturbating like he was.