Azmodeus

Born the Archdemon Azmodeus, he was a peaceful demon, who often spent his time helping out humans with whom he coexisted with tasks involving excessive strength. When the Other World was discovered, he fell in love with Tsuki Aya on sight. As the years went by, his love became obsession, driving the gentle demon mad. Filled with insanity, he slaughtered Aya's family to prove his loyalty to Death, presenting her with the remains. This horrified her, and as she held her sister in her arms, Azmodeus realized what he had done. He fled, shutting himself away. As time passed, his madness grew, to the point when he threatened The Council of Archangels with war, unless Aya was given to him. Denied this request, he declared war on Heaven, dooming both races to extinction.

Being the only immortal Archdemon, he too survived the desolation of Hell. Disguised as a human, he used his influence and wealth to assemble the Yamakawa Organization, which watches over and protects the remaining humans. He is described as a wonderful human being, but his true motives are to capture and enslave Aya. He seeks to obtain the Oblivion Sphere to reset his own dimension to rule it as well as the Aftermath, with Tsuki by his side. He is quite insane, sending loyal soldiers to die without second thought or concern for their well-being. His true form is an enormous demon made of living shadow. His abilities include shape-shifting, and brute strength.

His name means 'Devil of the Mountain Rivers' in Japanese. He is named for Azmodeus, Demon of Lust.