Poob was a monster employed at Horville's Hut of Horrors. He only appeared for a short time while Horville was talking to Wicket Wystri Warrick and in Wicket's dream. Poob looked like a small green ball with a long tube-like nose and hair along his spine.
P.S: It's poob, not ploob.
"Hey Poob, how's it going?"
"POOB"