I'm a big fan of cryptids and spooky folklore, especially American. Belle is inspired by the strange creature spotted and shot at in the beginning of the Bell Witch haunting (described as a black dog with the head of a rabbit), along with the cryptid "Old Green Eyes". Both legends of Tennessee, kind of like an American Black Shuck.

When she's not spooking farmers she's lurking in graveyards.
Character "theme" Meet Me in the Woods