Lucifer

Lucifer, also known as The Devil, Light Bringer, The Morning Star, and Satan, was the second of the four Archangels created by God and was his favorite son. He is also a fallen archangel, and the first fallen angel. He is one of the main characters of the series. He is the original ruler of the Demon Realm and the creator of demons, seen by them as a father figure and their god. As the second-born Archangel, he is the younger brother of Michael, and older brother of Raphael and Gabriel.

According to Gabriel, Lucifer is, or at least was, God's favorite and most beloved celestial, but when God asked for all angels to bow down to humanity, Lucifer refused both out of jealousy and wounded pride over being commanded to bow to what he saw as a broken, flawed, and murderous species and no longer feeling he was God's favorite creation. This was caused by the Mark of Cain corrupting him and boosting his dislike towards humanity. He waged a war against God but was eventually cast out of Heaven by Michael, and later banished to the demon realm by Michael, both times on God's command.

Personality
Lucifer was once the most beautiful and beloved Archangel in all of existence. God loved Lucifer the most of all his angels. Because of his elevated status among the other angels, Lucifer was very proud. When humanity was created, due to the Mark of Cain corrupting him into jealousy, he was unwilling to accept that he was no longer God's favorite. When God commanded all those of Heaven to love his new creation more than himself, Lucifer refused. Lucifer pleaded: "Father, I can't. These human beings are flawed. Murderous!" Lucifer continued his disobedience, asking Michael to stand by his side in his rebellion against God's orders. Michael refused Lucifer's request, and under God's command, Michael cast Lucifer into the demon realm.

Lucifer claims that he never lies or even tricks, because he does not have to, as he has said, "I will never lie to you. I will never trick you." Despite this, Lucifer is largely manipulative and has been proven to mislead on occasion, suggesting that this was more of a ploy to gain trust, rather than an actual commitment, and he would bend this rule when it's to his advantage. Furthermore, Lucifer tries to gain sympathy from his opponents by claiming that he is truly a victim and was justified in his actions.

Lucifer shows concern for his fellow angels, though it is the archangels he loves most. Lucifer was remorseful when forced to kill what he believed to be Gabriel and was disappointed when Michael berated him. When preparing to fight his older sibling in their pre-destined battle, Lucifer pleaded with Michael to "walk off the chessboard," but Michael remained determined to fulfill his destiny and serve God.

Gabriel criticized Lucifer, describing his actions as "one great big temper tantrum." Death also made similar observations, as he called him a bratty and petulant child with daddy issues. Lucifer is also arrogant and extremely vengeful, taking his betrayal and hatred out on the entire world without any remorse. Nonetheless, Lucifer sees himself as a tragic figure who was punished for being right. He refuses to accept any blame for his actions and suggests that God intentionally made Lucifer the way he is, asserting that "God wanted the Devil."

Lucifer is also highly cruel and barbaric to those who get in his way, and despite his claims of being the victim, he has no qualms about killing anyone who angers him, even if he has no true reason for killing them. He slaughtered an entire town by sacrificing the women and children and then having his demons possess the men before killing them just to raise a Horseman.

Lucifer has a sense of humor equivalent to Gabriel and Balthazar, rare in many angels. He can be sarcastic and casually indifferent, usually a testament to his arrogance. This highlighted particularly in Tsubaki's hallucinations of him, where she sees him as constantly shedding a snarky and wisecracking light on Tsubaki's everyday actions. When reunited with Tsubaki in the Demon Realm, Lucifer proves to have a comical side, going so far as to dance during a fight with his enemies.

While Lucifer is angry with God for imprisoning him, he feels that it's a family issue. After seeing God for the first time in eons, Lucifer initially seemed uncertain on how to react, but soon began to act somewhat like a petulant child, demanding an apology and locking himself in Tsubaki's room when he didn't get one. However, after God actually apologized and explained his behavior, Lucifer forgave him and the two reconciled their differences.

Quotes

 * (To Tsubaki Tachibana) "Maybe I'm scared because you mean more to me than any other person. You are everything I think about, everything I need, everything I want."