Duke Everlue is the main antagonist of the Daybreak arc—a corrupt politician who runs the town of Shirotsume with an iron grip. He's exactly as pleasant as that sounds.
The guy's a walking contradiction wrapped in delusions of grandeur. He constantly brags about being cultured and superior to literally everyone around him, and he's built up this massive book collection to prove it. Except Lucy straight-up calls him an enemy of literature because he blackmailed novelist Kemu Zaleon into writing a novel where Everlue gets to be the hero. So much for being a book lover.
Beyond the pretentiousness, he's aggressively greedy and possessive—if he owns something, it's his, and he won't let anyone near it, even if he thinks it's garbage. He also has a genuinely disturbing sense of beauty; he's into women most people would call unattractive, while he dismisses conventionally pretty girls like Lucy as ugly. It's telling that the narrative doesn't try to make sense of it.
Combat-wise, he's a mage specializing in Diver magic, which means he tends to show up unexpectedly by bursting straight out of the ground. As for his Celestial Spirits, Virgo used to be his before Lucy eventually claimed it.
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