Not much to add since this is pretty early on the process.
The colors are a bit cold overall, is she supposed to be scary? if not, it'd do well to add some warmer color, or alter either the green or blue to a more complimentary color.
Also, the design is a bit bland. Maybe you could do something fun like adding "ghost" shackles that connects them to her. On a serious note; It's in its early stage, so looking forward to see what you'll do with it!
