Cerberus was the kind of dog you would expect the God of hell to own. He had not only three heads but also a mane of snakes, dragon's or snake-like tail and the claws of a lion. Cerberus would allow those who had died entry into Hades, but stop the living--and he would not let the dead leave. However he was not above occasional being bribed or charmed. He is a guardian and protector, once he makes a decision he won't back down, unless you bribe him. LOL