The rulers of the Three Clans in Dance in the Vampire Bund Rozenmann, Ivanovic, and Li are all nasty customers, with Ivanovic being the most overtly brutal of the lot. In the past, the three destroyed and usurped all the other great vampire clans before murdering their sovereign, Queen Lucretia, and only sparing Lucretia's young daughter Min as a future tool for breeding for one of them. While Li hasn't been seen as much, he, Ivanovic and Rozenmann participate in a contest to determine who has possession of Mina: by sending their best assassins after her love interest Akira with the winner taking the prize, and subjecting Mina to a degrading chastity test so she knows she is the property of the three.
Ivanovic, the most vicious and unhinged of the three Lords, leads a brutal attack on the Bund to capture Mina for his own pleasure. Once there, he deliberately targets civilians, and has the innocent fangless vampires executed to draw Mina out of hiding. He also uses as shock troops werewolves he's tortured into feral beasts that have forgotten their own humanity. Ivanovic at points attempts to rape Mina when he can and has a disturbing taste for young girls, not caring that Mina is in her younger body as opposed to her adult form; he even declares he'll only enjoy her adult body after he's had his pleasure of the younger one. In the past, he was also Grigori Rasputin and drove Russia into chaos and ruin. Mina barely rescued Grand Duchess Anastasia from being dragged to his bedchambers at the end.
Rozenmann, the most elegant, handsome, well dressed and polite of the three Lords, is also the most intelligent and manipulative. He tricks Ivanovic into invading the Bund, knowing the death and destruction that will result. Planning for his fellow Lord's death, Rozenmann set up Mina to be kidnapped and replaced by a doppelganger whose terrorist attacks he was secretly financing and patronizing. With Mina in his hands, Rozenmann has Akira killed (though he was Faking the Dead) solely to break Mina further, and injects her with a drug to freeze her in adult form to rape her later. While Ivanovic is a wild, furious warlord, Rozenmann manipulates nearly every bad thing to happen in the series, with nary a care as to the many innocent lives or mental trauma he leaves behind him in his quest of domination.
The vampire crime boss Gabe from volume 11, while a comparatively minor villain, uses his short screen time well. Gabe is a vampire sworn to Rozenmann living in New York where he's a vampire, pedophile and maker of child pornography who routinely taunts a stripper about paying a visit to her daughter Susy, who can't be more than six. After he learns the stripper is sheltering the runaway Mina, Gabe violently murders her friend and storms her apartment, immediately noticing how Susy is prettier than he imagined and attempting to seize her before Mina stops him. Gabe uses Susy and her mother as hostages so Mina surrenders under promises they won't be harmed. While Rozenmann's honorable werewolf retainer Gerhard is willing to give the assurance, Gabe makes it clear he has zero intention of not coming back for Susy and when Mina asks to feed, he comments he thought her child form was much hotter and if he can have Susy when Mina is done. Mina remarks he has mistaken her grievously before she rips his throat out, commenting his blood is as foul as his soul.
Radovan Elichenko in life was a Serbian war criminal who, during the Bosnian wars, led his troupe of soldiers into a village while the men were away and slaughtered the elderly and the children. The women suffered worse. Any woman in their teens or over where taken and subjected to endless rapes and tortures. To escape justice, Elichenko became a Cudoviste or monster in the Slavic tongue-a vampire. He then joined Lord Ivanovic and carried out "purges" of any leftover clans in Ivanovic's territory. After fleeing to the Bund and betraying Ivanovic to gain sanctuary, Elichenko was confronted by the father of one of his victims who had become a vampire to hunt Elichenko down. When presented with a picture of the girl he'd raped and tortured, Elichenko sneered he'd done "thousands of Bosniak sluts" and only remembered them by how they looked "down there" before mocking him about having probably slept with his daughter because "Muslim men love to control their women." He then proceeded to assume his true form to kill him, unaware that the rage inside a grieving father was far more powerful than Elichenko knew.
The side story "Memories of Sledgehammer" brings us Friar Bolton, the most evil human encountered in the series thus far. The leader of a secret order of vampire killers once employed by the Vatican, Bolton murdered his more reasonable superior to take over the group. When a journalist who knew the truth fled, Bolton had him viciously tortured and nearly murdered Reiko, the man's daughter, to make him talk before Seiji Hama saved her. When serving as aide to a Colombian politician, Bolton empowered Cartels to commit crimes over the country and kidnap his own employer's daughter with no intention of returning her alive. When Seiji saved her as well, Bolton had him captured and tortured by the Cartel with his limbs removed, his eye and ears gone and his skin flayed before he was recovered by the vampires and placed in the Artificial Beastman project to heal him. In the present, Bolton engineers a series of terrorist attacks with no regard for collateral damage and violently whips his best agent, his predecessor's daughter Clarissa, with intent to send her on a suicide mission to dispose of her. When he faces Hama, he finally attempts to murder the man himself, along with Reiko when she intervenes. When Clarissa fatally poisons him, Bolton uses the last moments of his life to rant about how only he has the vision to see the extermination of all who stand against his ideals and how her father was too weak to see it.