Captain Doody is a demon who possessed Nick "Nicky" Diamond Jr. and a minor antagonist who appeared in Celebrity Deathmatch.
He was expelled from Nicky Diamond Jr.'s body by The Undertaker who saved Nicky from demonic possession.
Captain Doody was seen when he possessed Nick Junior's body to antagonize Nick Diamond Sr. Nick Jr. was then cursed by this demon which made him puke. Captain Doody then used Nick Junior as his host to fight The Undertaker, but The Undertaker has a plan to save Nick Junior and expels Doody from his body, and then used the Tombstone Piledriver to defeat Captain Doody.
The Undertaker then uses his signature taunt, the cutthroat, to expel Captain Doody from Nick Junior's body by banishing him back to hell, leaving Nick Junior with no memory of being possessed. Nick Junior then reunites with his father to impress The Undertaker and Captain Doody possesses a helpless popcorn guy named Phil.