Cerberus

Cerberus is a Mister Gutsy patrolling Underworld

Background
Programmed and maintained by Winthrop, Cerberus serves the ghouls of Underworld as protector and "guard dog." While it has been programmed to preach equality of humans and ghouls, its personal opinion of ghouls differs greatly, and only its combat inhibitor keeps it from turning on the ghouls.

Appearances
Cerberus appears

Behind the scenes
In Greek mythology, Cerberus guards the gates to the Underworld, preventing the dead from leaving.