John F. Kennedy. Edit
John F. Kennedy is a very rude ghost and former President of the United States, he often harrasses Cory and the gang while they are in the house, especially Cory, who he frequently will say his trademark quote "Dat Cory Assss" to. New York City's John F. Kennedy International Airport is named in his honor.
John F. Kennedy had an entire episode dedicated to him Season 7 Episode 4 "The Shrekle Shuffle" where he has an entire 25 minute arguement about religion and Corys sexual preferences which leads to Shrek punching him in the Ghost Jaw.