I don't have a video of it happening but when I was in the computer room at college my classmate placed his hand entirely around my cock through my jeans "you've got a big cock" little did he know I was 5 and a half inch's, I had never gotten any vibes off him or that he was open to gay stuff, when he suddenly placed his whole hand around my cock it was the biggest shock of my life.

I didn't like it at the time, it was Invasive and Terrible at the time, but over the 10 years since it has quietly turned me on for years after.