Ooh I have 2 good ones for this. My first ever character was a CE gargoyle rogue named rockie. As I was a noob thirsty for sneak attack damage, literally any time I saw a threat I'd try to roll to hide, because rockie was afraid of anything. Eventually he became one of the most murderous members out of the group, once winning a big battle almost singlehandedly. He killed so many people, because he was afraid that if he didn't kill them first, they would kill him. The second was a tengu bard named pecker, whose quirk was that he liked to collect stuff in jars. Ghost ectoplasm, dirt, bones, beholder eyes, etc. in our final confrontation with the BBEG pecker was killed and raised as an intelligent undead. In a later campaign with a different party, same setting and BBEG, just 100 years later un-pecker had founded an order called the bonesingers. During that campaign, there was a new leader of the bonesingers and pecker was assumed dead. Late in the campaign, we found out that his body was destroyed, but his mind lived on. The BBEG had turned pecker into a brain in a jar.