I like the sound of it. It's a cool name. I think it works well for a character. It might be harder for an actual boy to have this name because people might think that
Anaiah is a girl since the name is uncommon and looks and sounds like it could be a girl's name, but then again, it's close enough to other more familiar Biblical boys' names ending in -ah, such as
Elijah and
Isaiah, that it might not be that much of an issue.