My first interaction with the bully was in 9th grade. He failed 9th grade and had to repeat it. We were not only in the same class, but we were also put sitting together. The guy bullied me for being gay, overtly skinny, smart, basically anything you can think of. There was also some physical violence, as well as some sexual innuendos (he grabbed my butt a couple times and would rub his genitals to catch my attention. At the time I strongly believed he was gay, and today I have the confirmation).

The following year, we both moved on to 10th grade. One afternoon, at the end of Chemistry class, the whole class was acting out of control, so the teacher called the principal, who punished us by keeping us in the classroom for 10 minutes, shutting the door and staying outside the room. In an act of rebellion, I hit the door really hard with my palm. The teacher heard it and came back inside to give me something I can translate as a "red absence" (it's a harsh form of punishment for bad behavior. Worse than this is suspension and expulsion).

The next day, the head teacher assigned to our class asked us about what happened. At this point, for whatever surprising reason, most of my classmates had had enough with this guy’s bullying and didn't seem to like him anymore. So, they all told me to tell the teacher that me and him hit the door together, and they would support me. As a result, the bully also got a "red absence". He got heavily upset to the point of calling his father to the school to talk to the principal. I was asked to make a statement in front of his father and I lied to this father with a straight face.

A few months later, the bully got himself in another problem. He was making money piercing ears after school inside school premises. One teacher found him doing this, and the got another "red absence". Two "red absences" in the same year means expulsion. He got expelled and I was left with one less bully.

Edit: Thank you so much for the outpouring of support! I have a few more stories I’ll share on this sub in the future.