Adramelech was a form of sun god, the center of his worship was the town of Sepharvaim and was brought by the Sepharvite colonists into Samaria. Like other pagan gods, Adramelech is considered a demon in Judeo-Christian tradition. According to Collin de Plancy's book on demonology, Adramelech became the President of the Senate of the demons. He is also the Chancellor of Hell and supervisor of Satan's wardrobe. Being generally depicted with a human torso and head, and the rest of the body of a mule or peacock.
A poet's description of Adramelech can be found in Robert Silverberg's short story "Basileus." Adramelech is described as "The enemy of God, greater in ambition, guile and mischief than Satan. A fiend more curst — a deeper hypocrite." In classic literature, Adramelech is a fallen angel, vanquished by Uriel and Raphael, in Milton's Paradise Lost.
"Chancellor of Hell and supervisor of Lucifer's wardrobe. Has the body of a mule and the plumage of a peacock. Worshipped by the Ayssrians sic, who sometimes offered children to him as a sacrifice."
—Shin Megami Tensei IV Apocalypse compendium
Adramelech is the first boss of the game, appearing before Nanashi, Nikkari, Manabu and Asahi. Having been ordered to purge Tokyo clean of the weak by Lucifer, he attacks with a horde of Fallen demons. During the fight he kills Manabu with his fire magic and finishes Nikkari afterwards. He kills Nanashi only for him to revive and fight back. His horde is killed in the second fight, but he retreats before he could be killed.
He appears alongside a Power on Lucifer's orders to help Nanashi oppose Shesha in the first fight against the serpent. Adramelech is later fought in front of Tsukiji Konganji, where he dies in their final encounter.
After defeating him for good, Adramelech is unlocked for fusion in the Cathedral of Shadows. A special fusion of Tonatiuh, Kelpie and Murmur will summon him. Adramelech can teach Nanashi the Madness Nails and Eat Whole skills through his Demon Whisper, but his Hellish Brand skill cannot be passed on in any way. He benefits from learning Fire and Physical skills.