Immortals

The Immortals (不死者 fushisha) are a group of people who attained immortality, stopped aging and became impervious to injury.

All immortals must follow a set of rules and guidelines. Although they are able to use a false name for temporary introductions to mortals, their bodies reject all attempts to establish lasting false identities. In addition, they must use their real names when speaking to another immortal. Immortals can transmit information and images to another immortal by placing their left hand on the other's head and thinking about the information or image. To kill an immortal, another immortal must "devour" them by placing their right hand on the other's head and thinking "I want to eat." In addition, the more often an immortal is injured in a certain way, the faster they will recover from that injury.

History
The elder immortals known are an old man who told Maiza Avaro how to summon the demon and Renee Paramedes Branvillier.

The original immortals were a group of about thirty alchemists who were traveling aboard the ship Advenna Avis in 1711. Aboard the ship, they summoned a demon in the hopes of gaining immortality. They are successful and the demon gives them the Grand Panacea. Their leader Maiza Avaro is given the formula for the elixir. Later, the group decides they must keep immortality to themselves. Szilard Quates disagrees and devours thirteen of the alchemists, obtaining half of the formula Maiza gave to his brother, Gretto Avaro. Realizing the danger Szilard poses to them, they scatter throughout the world. Szilard devours five more of original immortals, bringing the total to eighteen, before he himself is devoured.

A second group of immortals is created in 1930 after Szilard manages to recreate the elixir, but loses possession of it. After it is passed around Manhattan by gangsters believing it is alcohol, Isaac Dian and Miria Harvent, the three Gandor brothers, Firo Prochainezo and all of the Martillo executives drink it at a party.

Those who drank Szilard's incomplete immortality elixir become partially immortal. Although they can be killed through devouring, they cannot devour back and do not stop aging.

Demons

 * Ronnie Sukiart (Advenna Avis' demon)

Homunculi

 * "The Poet"
 * Adele
 * Christopher Chareau de Red
 * Ennis
 * Hong Chimei
 * Leeza Laforet
 * Sham
 * Sickle
 * Reil

Grand Panacea

 * Elmer C. Albatross
 * Czeslaw Meyer
 * Denkuro
 * Fermet
 * Gretto Avaro
 * Huey Laforet
 * Maiza Avaro
 * Nile
 * Renee Paramedes Branvillier (before Advenna Avis)
 * Sylvie Lumiere
 * Szilard Quates
 * Victor Talbot
 * Zankuro

Cure-All Elixir

 * Berga Gandor
 * Keith Gandor
 * Luck Gandor
 * Isaac and Miria
 * Several members of Martillo Family, including Firo Prochainezo, Randy and Pecho

Incomplete immortals

 * Dallas Genoard
 * Dallas' Gang