I read this while sitting in the dentist's chair for three hours getting a new crown. Great dentist-chair reading. Great reading. Is this a children's book? It should be. It had that peculiar didactic tone that children's books take when they're dealing with "difficult" subjects. Whoever it's for, I would give this to children for sure. 
 I know this is a prequel (first in a series? IDK the writing order) to at least one of LaValle's other books, The Devil in Silver,- and I immediately bought that one and started it. I'm a bit scared though- the ambiguity of (view spoiler)[what happened to Loochie (hide spoiler)] will probably be definitively explained, and that's part of the beauty of the book!