This book guys. This book.
It could have gone wrong at a dozen different points, but Shultz deserves all the praise for keeping The Dark World classy and mostly devoid of the tropes I dislike in YA.
This story world is awesome. There are ghosts and demons and warlocks, half demons and half warlocks, and people with wings. Wings!
It was never confusing and the author took the time to make sure everything was internally consistent. I think we could have spent a little more time exploring the Dark World, but I guess that's what the sequels will do.