Prince Severin von Phoenix (セブラン Seburan) is one of Hime's brothers, the fifth prince of the Royal Kingdom. His appearance is that of a bishōnen with sharp eyes and blond hair, and he wears a black coat with feathers woven at the shoulder. He makes the opponents he has killed into his blood warriors, and has turned an entire town into zombies which is forbidden. He lost in a duel with Hime and was killed.
Severin was the one who unleashed Zombies to wipe out Lillianne's retainers, which was forbidden by Kingdom Rules. He used to have a cat which he named after Lillianne to tease her. He used it as a plaything then presumably murdered it in cold blood. He killed Mikasa and later revived her as his blood servant.
Initially, Severin was portrayed as a calm, laid back Master who seemed rather amused by the surrounding events of his first appearance (a zombie outbreak). His darker side surfaced when he was suspected of framing Hime for the zombie attacks, which is further supported when Hime's lawyer revealed that her realm was destroyed by a similar event in the past.
He is able to keep a cool face at all times, even during the duel with Hime. He repeatedly insults her, even mentioned the cat whom he tortured and killed was named after her, angering Hime and gaining an advantage over her. However, his calm-and-collected facade is quickly dropped when Hiro, calling out for Hime, enabled her to regain composure and fight back; Severin panics and gets rapidly pushed back by his advancing sister, revealing his cowardly nature.
Severin does not hesitate to use dirty, underhanded tricks to eliminate his opponent. He once used the forbidden magic to raise zombies and devastate Hime's realm, then again to lure her out of hiding so he can kill her. The outbreak is then blamed on Hime herself to eliminate her politically, but ultimately fails and the two challenged each other to a duel. At the climax of said duel, his left arm was revealed to house a gun that was not permitted to use, but he used it anyway to try to kill his sister.
Severin is also quite manipulative, as he has somewhat complete control over his blood servant, Mikasa, whom he murdered and raised as his own warrior.