Deathman

Deathmen (妖死族) are a race of Undead Majin. Their bodies are composed of the power and flesh of thousands of corpses created by the forbidden magic "Birthday" (妖死冥産) and are Demon Lord-level monsters.

Appearance
Deathmen, as high-level beings, possess an appearance based on their own self-image. This results in an appearance that is identical to that of the individuals previous life or otherwise desired form. They usually possess a more monstrous second form influenced by their bodies essence as an undead, resulting in a strange zombie-like appearance.

Characteristics
Deathmen all have a unique trait of being able to connect their Astral Body to the ley lines in order to keep their consciousness and memories protected. They cannot truly die as long as their Soul is still intact, even when their physical body is destroyed.

Trivia

 * Kagali was the first known Deathman in the series chronologically, created by Jahil's "Birthday" spell.
 * They are different from most Undead, in that they possess full flesh and are equipped with biological functions, the extent of which is still yet to be known.
 * While Deathmen are able to live with just their Astral Bodies and connect their consciousness to the leylines, it is also a curse as in some cases they cannot possess the host if they already have an existing Soul, such as the situation with Kagali, who was forced to share a body with Yuuki Kagurazaka till she was given a Homunculus body that was not contaminated by any Souls.
 * Compared to other Majin, their race seems to be the lowest population-wise. It is possible that Deathmen cannot reproduce at all, given that they can only be created through the "Birthday" spell and that their essence itself is that of an Undead.
 * Given Clayman's transformation into the "Crazy Pierrot" form, it is possible that Laplace and the other members of the Moderate Harlequin Alliance also have such an ability. However, this seems unlikely as the form is more combat oriented and given Clayman's weak power, it is possible it was given to him for self-defense and offense solely, and that the other members already possess powerful combat capabilities.