Yeah curiosly the first one was when i was 11 yrs. By that time i had no sexualization over ass but here it comes:
I was walking, when you walk you move your arms, I pass next to a girl, i touch her ass accidentally. I say her sorry and that it was accidental. She slaps me and say to the class and the teacher that i did harass her.
Literally by that age i didn't even get excited by an ass, but i was the less beta and probable ugly.
I have another storie. And probably there are many more bc i've been blocked from sm multiple times but i think gils talk them behing my back