There is plenty of violence, and some creepy parts.

Joker is not directly involved for most of the show, and it sets him up as by far the most extreme of the villains.

Most of the show seems fine to me, but there are two specific examples I can remember that are worse than the flesh melting:

• bloody shock humor S01E11: spoiler if you watch more than a few seconds
• kinda jump scare from S02E3: cause I'll take blood over crisps any day