Brody, Rob and Eddie aka The Metal Dudes are a cabal of recurring creeps on Todd & The Book Of pure Evil. The dudes are always scheming to get Todd to accept his destiny as the pure evil one. The Dudes also form the band ask not the innkeeper.
Old photos found in their car and a flashback involving Jimmy seem to suggest that they are immortal and that there have been previous pure evil ones. It is as of yet unknown exactly who or what the metal dudes are or which powers they possess. They can transform into a slutty girl called Nikki to pop a particular pure evil one's cherry. Almost two decades ago the dudes were after Jimmy who used the book to bar them from Crowley High. They also used their Nikki form to seduce Jimmy. Recently they seduced Atticus into their service and convinced him that he was the Pure Evil One.
The dudes were extremely disappointed when Todd refused to destroy the world and shocked when he called them losers.