The sensitive, bitchy, neurotic Betazoid who used to be a patient of Troi's. Betazoids have the unwanted telepathic reception of everyone's thoughts turned way down naturally at a young age as they grow, but his never got turned down, so he went a little nuts.
He mind-melded with the orbiting "ravioli" creature in the one episode. I can't remember the episode name or the character's name
