Billy Kessler is a fictional character in the comic book series G.I. Joe: A Real American Hero. He is the son of the main villain of the series, Cobra Commander, but fights against his father and the forces of Cobra Command, learning martial arts under the tutelage of Storm Shadow, who helps him after a botched attempt on Cobra Commander's life. While still a boy, he loses an eye and a leg when a Cobra operative destroys a car in which he is riding, and after recovering he goes on to become a member of his father's greatest enemy, the G.I. Joe team.