It wasn't an OC, but I still remember this one person played a character so out-of-character it was ridiculous. Every post I saw, public or private, was either smut-bait, being excessively toxic to their "loved ones", threatening harm/suicide (in-character, of course), or being unnecessarily violent (like punching someone through a wall because their food order was incorrect, I think?)

It got so uncomfortable that group chats had to make alternate group chats just to exclude them - which was rude, but lord, you could not have a normal interaction with them around. I tend not to be judgemental, but they were always trying to start things with people out-of-character, too - so at that point, I do get a little judgemental I guess