Nyaa

A black cat that is the protagonist's familiar.
He started out as a cute kitten, but he grew up in a flash and is now a sharp tongued straight man.
He's always at the protagonist's side making cheeky remarks.
His full name is "Nyaa Onyaate Garinyaate Grinyaal Stinyaani Manyaani Minyaal Renyaano The Third", That's too long so he's just called Nyaa.