Role in the series
Although Dedede is a primary antagonist, he is not necessarily evil. Several of his deeds are performed when under possession by some other entity — three times by the Dark Matter, once by Yin-Yarn, and once by Taranza. Whenever he is the villain of his own volition in the games, however, it is usually due to selfish mischief, such as stealing food or trying to prove himself better than Kirby. Despite his greed and selfishness, he sometimes has pure intentions behind his actions. His role as the antagonist of Kirby's Adventure was ultimately to protect Dream Land from Nightmare by hiding the Star Rod. He has also willingly helped Kirby in Kirby 64: The Crystal Shards, Kirby's Return to Dream Land, and the Subspace Emissary story of Super Smash Bros. Brawl. Dedede is sometimes seen to be on friendly terms with Kirby, especially in the more recent games. He shows no apprehension towards helping Kirby in Kirby's Return to Dream Land and is visibly very happy to see him towards the end of the Subspace Emissary, even going as far as to run up to hug him. Despite this, he is still the main antagonist (or the tertiary but more active antagonist compared to Customer Service and Nightmare, who both prove to be a much bigger threat) in the anime, although it is revealed near the end that he enjoys their one-sided rivalry to an extent and that he does not actually wish for Kirby to die, which eliminates his role as a villain at the anime's conclusion.
Although King Dedede's authority and influence over Dream Land is seldom questioned in the games, events and descriptions in several spin-offs and references including Kirby: Right Back at Ya!, and Dedede's trophy description and a Codec conversation with Colonel Campbell in Super Smash Bros. Brawl suggests that it is highly subjective depending on context. King Dedede himself takes it for granted, and his army of Waddle Dees serve him and staff Castle Dedede. Meanwhile, other creatures happily go about their business with or without him. In Kirby: Right Back at Ya!, when his people choose to defy him whenever he oversteps his bounds, he has little to no enforcement of his authority to stop them, short of ordering monsters from Nightmare Enterprises and having it backfire on Escargoon and himself.