This is how it goes, was late to college today and cant find my underwear. In the hast to get fast, decide not to wear underwear when putting on my jeans this morning. It was fine during the dressing up hence i zipped up very slowly and carefully. But, after two hours of lecture, i really need to go to the toilet to pee. As i entered the mens room, nobody was there and i have the privilege to choose the nearest urinal as I cant hold it anymore. I stood straight at the urinal, in the position ready to shoot-out, and yanked down my zipper as fast as i could. Fuck! i forgot i am not wearing underwear and a very sudden and sharp pain struck onto my dick skin when the zipper got stuck whilst on its way down the track. The zipper only goes down half way, with my dick skin caught underneath the zipper plate and was terribly trapped in between the metal zipper plate and the teeth of the zipper. then, unzipping attracts more skin into the zipper, zipping up caused double pain to the trapped skin.