Charles Foster Offdensen is Dethklok's manager, legal counsel, and CFO, the latter also incidentally being his initials. He acts as the voice of reason against Dethklok's constant disregard of law and logic. He acts as manager, lawyer, and advisor to Dethklok, protecting the band against everything from slowing record sales to themselves. Offdensen is one of the few individuals seen to interact with Dethklok for any significant length of time and evade subsequent mutilation or death.
Offdensen is a "dark parody" caricature of band-managers, being "all about business;" he reacts with general apathy to the mayhem caused by Dethklok, his only concern seemingly being the legal or financial ramifications of their actions. Similarly, he shows little more than slight annoyance when the band insults him in one way or another. Despite his attempts to curb Dethklok's violent behavior (at least in public), Offdensen has just as much potential for violence as the band members themselves should the situation call for it. However his violent acts are always quite calculated and direct to a surgical degree and done with clear objectives in mind to protect the band — unlike the band's violent actions and effects which tend to be extremely random and usually quite accidental. He has no problem ordering others to be beaten or killed (Dr. Rockzo in particular, whom he orders to be beaten and tortured twice). General Crozier warns Dr. Rockzo to "stay away from [Offdensen], he means business."
Offdensen also has secret contacts with the leaders of the United Nations, because so much of their economies depend on Dethklok sales; this allows him a global license to instantly and secretly trace, capture, torture and imprison all those who illegally download or record Dethklok's music. These victims are simply publicly listed as "missing," but are secretly imprisoned and tortured at Mordhaus, where they are driven to insanity by forcibly exposing them to Dethklok's music at extremely high volumes ("Dethvengeance").
Offdensen displays exceptional skill in close-quarters combat in several episodes. In "The Metalocalypse Has Begun" he single-handedly disarms and almost kills the Metal Masked Assassin, despite the latter being much more physically imposing. When he is surprised, badly beaten and thrown through a window several stories high in their next encounter in the episode "The Revengencers", he manages to land on his hands and feet without injury. In "Dethsources", he has a fencing match with Melmord Fjordslorn to determine who would remain as Dethklok's manager, having insisted that the only way to separate him from Dethklok would be to kill him. After a lengthy battle, Offdensen barely manages to stab Melmord and force him off of the top of Mordhaus' Dragonspire, causing him to fall to his death on the train tracks below. A passing train moving into the compound annihilates the body.
Offdensen's knowledge of the conspiracy against Dethklok is unknown. His office has a safe containing classified information; however, the contents of the safe are never seen, as he catches Dr. Rockzo just before the act of attempting to film them. He uses high-tech radar and surveillance to monitor the band's safety during their ill-fated performance of Dethwater at the Gulf of Danzig in the first season finale; he likewise has an elaborate defense, escape and counterstrike prepared when military forces attack Dethklok.