could something be askew? Or bats flew, or something taboo or new or true. If it's silly, maybe he could be out past his curfew. He's a bag of bones without a sinew. Maybe he's a skeleton from a curse of voodoo. He could have a graveyard point of view. Perhaps he tasted a witch's brew. Maybe you could end the line with only a few, something he can't do, a pair of two.
I love my rhyming dictionary.