This happened many years ago in a small town in Iowa when I was younger and very impressionable, burning it into my memory and causing me to jerk off every time I think of it. The local theater offered a Saturday morning matinee for half price that I attended without fail. A mob of us gathered outside waiting for the doors to open so we could rush in and claim our favorite seats. Today's feature was a zombie flick.
Halfway through the scary movie a dirty, little man, obviously a vagrant, carrying a leather shoulder bag came down the darkened aisle to ease himself into a seat in the center row. We noticed the intrusion thinking it might be a tie-in with the Zombie movie, but when the man just sat watching the movie we forgot about him until we noticed he was playing with himself, fondling his big fleshy dick. We instantly forgot about the movie and moved nearer to the dirty little man, who by now we knew to be a pervert, to enable us to get a better look at what he was doing. With every eye on him he slowly began stroking his throbbing dick causing us to silently or audible groan knowing what sensual pleasures lay in those strokes. My body flushed warm when he increased the speed of his strokes as if he were touching my dick laying rigid and aching in my pants. I was not alone when my hand fell into my lap and I fondled my dick feeling not unlike a pervert myself. Looking around I saw some boys were openly masturbating keeping in rhythm with the motions of the dirty little man in his seat. He suddenly pushed his trousers to his ankles and fell into a frenzy of masturbation, the slapping of his fist against thighs echoed throughout the theater. Driven crazy from watching I let my pants fall to the floor and without fear of the consequences freely jerked off along with everybody else.
When the little pervert stiffened his body and groaned loudly letting a thick, ropey, stream of milky cum shoot high into the air to fall back onto his thighs and run down his fist, we all joined in groaning and shooting our load of jizz into the air to fall where they may, completely caught up in the decadent pleasure of the moment. The little man cleaned himself, pulled up his pants and left the theater, vanishing up the aisle and out the door. Some who had not finished were still beating their meat in a frenzy to catch up. Others were zipping up their pants. For weeks after the theater manager caught boys jerking off in the theater watching the aisle hoping the little man would reappear.