I've been obsessively watching Coraline lately (that movie is like candy for the right half of your brain) because I have an idea for a new story about a sort of monster that steals children. I don't mean like the Erklings that J.K. came up with, but something more sinister like the beldam in Coraline, which is apparently an actual concept.

I might just end up using a beldam for my story, but I'd like to consider all my options. Does anyone know of any myths or creatures that could fit this bill?