A person who is so vapid and devoid of a soul or emotion, they may as well be a zombie. They often work menial jobs and their speech ranges from inaudible squeaks and sputters to simple replies using the least amount of words possible.
Person A: "Clyde has been earning meager pay at the same job for five years already, is 24 and lives with his parents, he hardly talks, and prefers to spend his weekends drinking alone at some shitty dive. What gives?"
Person B: "He's a non entity, and he will suck the life out of you."