Fatso, also known as Atso is a former character who first appeared in First Day Of School!. He made his first appearance in First Day Of School!. He seems to be very fat, saying that his parents call him that as well. In The Love Potion!, Atso left the class for an unknown reason (his voice actor is no longer around, because Atso and his other characters are not needed). He was later killed off in Shrek's Coma!, and his body was used by Shrek during that episode.
Atso is overweight, hence his name. He has dirty blonde hair and brown eyes. He wears a vest with his belly sticking out.
Atso acts like he is fat and dimwitted and laughs maniacally all the time.