dairy vampire

Either some form of roommate or house guest who comes in and drains all of the milk from your fridge.

May come in the form of the extremely polite "gentleman vampire" who replaces your milk in abundance compared to what they drank, or the "Nosferatu" type that fiends upon all dairy in the house while leaving no consideration for others in it's path.

"I just bought that milk today! I can't believe that you already drank it all you freaking dairy vampire!"