Mortis

"My mistake was thinking I lacked a heart in this hollow body. Physically, speaking of course, I have no heart. Saying I do would simply be denial of my own anatomy. But spiritually, or metaphorically speaking atleast, I...have a heart."

- Mortis accepting his "heart" Mortis (モルティス, Morutisu) is an ancient Demon, formerly one of the Thirteen Calamities. He is the only one of the Calamities to go against demonkind during the Dragon Civil War, having grown an odd adoration for humanity. It is due to this reason that he wasn't sealed in the same manner as his fellow Calamities, instead being allowed to roam Caelum freely, but is cursed to spend the rest of his time only in Caelum. Should he ever cross the border of Caelum, and break his alliance with humanity, the curse would kill him instantly, turning him to ashes.

After over 400 years, Mortis has identified himself as a citizen of Caelum, residing in its capital, Praeter, even going as far as legally changing his name to John Hellsing (ジョン ヘルシング, Jon Herushingu). He functions as a sort of "guardian" for Caelum, being called whenever a great threat approaches the country, as such is also referred to as Shield of Caelum (盾のカエラム, Tate no Kaeramu).

Due to his growing passion and love for music, Mortis became a successful musician, being most famous for his piano play, among other known instruments. His reputation, while sufficiently better compared to 400 years ago, still has room for improvement as well, due to several people within Caelum who dislike his presence, believing it to be a curse, as well as a danger to everyone.

Trivia

 * Mortis has a heavy "death" theme to him, with his original power being named after the "Day of the Dead", and his name being latin for "Death", in addition to the name "Hellsing" being a reference to Abraham Van Hellsing, who appears in the novel Dracula.