I'll add my 2 cents, though I'm not an expert on book covers either. My question to you is: what does your possessed poodle do? Would it be possible to have a pile of carnage in the background, and a much more sinister close up of the face blocking part of the view? Maybe a burning building or car? A poodle is not a werewolf with all that curly hair, so I don't see any worries there.

Right now the poodle looks too innocent and cute.

Is there a person who doesn't believe the poodle is evil? Is there a scene of said person discovering the carnage? If so, an image of him/her could be running toward the evil, tooth bearing face, as Nathan suggested.

Another thought, if there is a person, would having the dog being held while we can see the snarling face something more suited to the story? I say this because of the title, but I don't know the story. "Hannah" does not suggest a rabid evil dog, so the image is what you'll need to convey that, and maybe a red, blood dripping title. Could even have a paw slash through it.

I do know photoshop rather well, so if you like the feedback, PM me with a query or something and maybe i can help. Nathan's daughter would be welcome to join in the adventure!!! (Not sure about the rights to said images though.)

Best of luck no matter what! I think a killer poodle sounds fun!