|Aliases||Son of Lucifer, Son of the Evil One|
|Voiced by||Matt Stone|
He is the son of the Devil. He comes from Hell to challenge Jesus to a fight with his father, Satan. Everyone at South Park Elementary makes fun of him and calls him "Fartboy"...although he winds up winning them over at the end by making fun of Pip.
In Damien, he joins the boys' class as the new student at South Park Elementary. He introduces himself as the son of Satan, a claim which is completely ignored by Mr. Garrison, despite his obvious evil powers. Damien is rejected from sitting with the main characters during lunch, and is taunted by Kenny and Stan. Outraged, he turns Kenny into a duck-billed platypus, then demands to speak to Jesus Christ.
Damien's father, Satan, challenges Jesus Christ to a boxing match, and everyone in town switches their bets to ]Satan, realizing Jesus doesn't stand a chance. One bet on Jesus remains, secretly placed by Satan himself. Initially, Jesus is horribly beaten, but Satan throws the fight, allowing Jesus to win in order to get everyone's money. Damien then returns to Hell alongside his father, claiming that he only performs evil because he has to. As Damien leaves, Stan and Kyle briefly lament that he will never be able to gain acceptance because he's always on the move.
Since then, Damien has appeared in the background of various episodes. He was also seen in the movie theater with other children watching Terrance and Phillip: Asses of Fire in South Park: Bigger, Longer & Uncut.
He is based on the character Damien from the 1976 horror movie, "The Omen".