what is a person who believes in afterlife judgement called?

A person who believes in afterlife judgment is often referred to as a "theist" if they believe in a deity that judges individuals after death. More specifically, terms like "Christian," "Muslim," or "Jew" might be used depending on the person's religious beliefs, as many religions have doctrines regarding afterlife judgment. However, if you're looking for a more general term, you might call them a "believer in an afterlife" or "believer in judgment after death."