ケルベロス

The three-headed beast that guards the entrance to Hell. Its terrible paws rend the earth asunder, crushing all foolish enough to stand in its way, while its fiery breath is capable of melting even the hardest of steel. ...At the moment, though, it takes on the appearance of a three-headed Corgi that acts as a pet mascot and is kept at Pandora's animal pen. Its fluffiness is a force to be reckoned with. [Source: MangaGamer]