Azalel was cast out of hell by his father lucifer when he failed to kill one of God's archangel named Myriel. It was because he fell deeply inlove with him that in the war against good and evil. He went against his fathers order and sided with the angels. In that war, muriel saved his life which led to his own death. He was then held in a mountain to reccuperate. And was let alone after thousands of years. He lived in the mortal world in hopes of seeing muriel's reincarnation. But what surprised him was Muriel's body did not actually perished. Instead, God sent his soul to be cleansed on earth until it has to ascend and be one with its body. He was tasked to protect that soul. But was also restrained from doing such things that would prevent its soul from being cleansed. And that includes him not letting his feelings get in the way of his mission. While preventing Muriel's soul from falling for him. Together, they will have to face foes that could not only end their lives. But also drive a wedge between them. In the end, azalel had to choose between covetting Muriel and losing him forever. Or sacrifice his powers to be human while letting Muriel ascend to heaven.