I don't mind the jokes but a few of my friends don't even make jokes half the time, just straight up bullying. I've had them mimic me but 100× worse and it'll go on for minutes. They'd just go "g-g-g-g-g-got a-a-a-a-a-a s-s-s-s-st-st-st-st-st-st-stutter" as an example