The Supervisor is a member of the slime-person alien race. They speak casually, but have a somewhat distant and cold personality - like an indifferent coworker. Much to their name, they teach and supervise the young slimes (a.k.a the players) as they clean, occasionally offering advice, commentary and observations on their progress.

They are also the NPC which guides the player through the Tutorial, so this role will have more lines than the others and may require more than one recording session for those.