I realized it in high school with my girlfriend. Started all when i became aroused from her desperately holding her pee back in the car one day while we were driving back to her house after school. She had been holding it for a long time. She was sitting in the front seat with her legs crossed with her hands in between her legs. Bouncing up and down groaning and moaning. I started getting turned on. When we got to her house she ran into the bathroom pulled her spandex shorts down and began peeing loudly with relief in front of me. She then saw i was turned on and spread her legs for me to see