... is the mind itself.
Saw my little kitty had grown up, and I immediately knew I had to make a dress-up with him! Everything happening in this scene - the ghost creatures mocking the cat, the muzzle around his mouth, the ropes and chain around his legs, and the terrarium it's all in - are meant to be sort of like metaphors, to show what fear can make you feel like.
Sorry for the sort of, uh, DARK theme of this dress-up... but hey, the category says Dreams and NIGHTMARES, right?