In Greek mythology, Cerberus (the hound of Hades) is a multi-headed dog that guards the gates of the Underworld to prevent the dead from leaving. He was the offspring of the monsters Echidna and Typhon and was usually described as having three heads, a serpent for a tail, and snakes protruding from multiple parts of his body.
Jared Cerberus gets his own story and his own Electus in The Hellbeast King series. His chosen one is Ella.
His brother sometimes calls him just “J”.