Clarion is a demon in the series.
The name was coined by the "alien contactee" Truman Bethurum, who wrote several books about his experiences with aliens hailing from the planet Clarion, which allegedly existed on the other side of the moon.
Devil Summoner: Raidou Kuzunoha vs. The Lone MarebitoEdit
Clarion had traveled the infinite space long ago, which exhausted it and led the entity to hide on the other side of the sun, sending a piece of its mind and body to earth in order to corrupt a human. It found Abe Seimei's body and became a parasite within him. Human will was strong, however, and it was only until a moment of weakness that it could corrupt him with the belief "Sacrifice the weak, to protect the weak."
An entity from beyond the stars brought forth by Abe Seimei by using the Behemoth born from the poisonous magnetite of his onmyodo, with Abe acting as its intermediary. It first appears in a shape similar to YHVH. It is only after Raidou pierced Abe's body with his sword that Clarion was able to take control through the eye that was part of Abe's body. The goal of Clarion is to dissolve human ego and have all mankind become a part of its body for eternal peace and salvation.
It has a attack called Lament of Creation, which rains down meteors upon the earth. Clarion can also unleash tentacles to attack the surface. Clarion is eventually defeated by Raidou Kuzunoha the XIV with the aid of all his demons and the sword Ame no Ohabari.