I don’t know if this is pro, but it is certainly more than petty.
In high school (10+ years ago), I was quiet and attentive in class. Teachers liked me. I wasn’t popular, but I had good friends. I say all this to explain that high school was relatively calm for me. I played sports, was on the student newspaper, and got decent grades. However, that all changed my second semester junior year.
I’ve always been a voracious reader. My freshman English teacher recommended I move up to the honors English track, so I did for freshman, sophomore, and the first half of junior year. Then I was put into Classical Literature my second semester junior year. I’ve always loved Greek and Roman stories, and had already read your typical high school classical reading list on my own. I didn’t mind reading them again until I met Ms. Umbridge. She put on a sweet facade, but she was downright evil. She also decided she hated me. I still do not know why, or what transgression I committed, but she HATED me. I assume it was my habit of sometimes nodding off in classes. At the time, I had undiagnosed thyroid issues, and was getting up at 5 a.m. for swim practice. I say sometimes, because it happened maybe twice a month total between all eight classes. I don’t remember nodding off in her class, but it could have happened.