[NSFW] How common is frotteurism?

When I was 12–16, one two separate occasions, I was essentially sexually assaulted by a random perv in a crowd. On each of these occasions, I was in public and in a crowd of people watching a street performer or something that engaged everyone’s attention. At some point, I became aware of something poking me, into my hip or butt cheek.. yeah, you get the idea. Ew.

Both occasions, I felt a smug energy from the guy doing it, like “Yeah, I’m getting off, what’re you gonna do about it?” I felt a gamut of emotions from shame to disgust to embarrassment. Anger and outrage came later. I was too embarrassed to make a fuss while it was happening and to tell anyone it had happened. Then, when it happened a second time, I felt really ashamed and like there was something wrong with me that had drawn this type of guy to me.

I thought I was the only one.. I had never heard of it happening to anyone else, and it happened twice to me!

Over Thanksgiving, my uncle randomly confided in me that this sexual crowd-poking had happened to him when he was younger. Suddenly, I felt worlds better because it wasn’t just me!

I’m curious now. In terms of sexual deviancy, does this sort of thing happen a lot?