what is the eighteenth angel? (not the movie), please help lol?

Answer 1

This was strictly made up for the movie. There is nothing about it outside of that.

Answer 2

Actually, though the movie and the anime thing make things a little murky, there is indeed an 18th angel.

In Kabbalah, the 18th angel (out of 72) is named Caliel, the angel of justice and innocence. It probably has little or nothing to do with the movie/anime versions, but it's something.

Most of the other versions I've spotted just get hung up on the evil angle--since 18 = 6 + 6 + 6, that angel is usually a bad apple.