Alterfloof

Alterfloof (floofinition) – 1. Housepet or animal with more than one personality. 2. An animal or housepet who originated in another universe. 3. Slang for an otherworldly behaving housepet.

In use: “Sometimes Maxine could be terrifying. She was an alterfloof, frequently cuddling and sweet, but then suddenly growling and baring her teeth at everyone, spreading fright through the household. No one knew what caused the shifts.”