moray eel

I would choose a moray eel, which everyone thinks are vicious. Really, they're just deficient in two or more senses - they can't see or smell well and therefore occasionally bite the hand that feeds them. My particular moray would be name Morey and I would set up a whole little swimmy paradise in one wall of my apartment for him. He would occasionally poke his creepy little face out at me when he wasn't feeling shy, or to scare off intruders. I would stock his tank with cheap but tasty fish and therefore avoid getting my fingers getting bitten off.