Male. He holds the name most coveted by demons, but he personally isn't fond of it. He styles his hair up because he doesn't want to look young. He asked Jiwon to give him a new name, but was rejected and continues to be called Lucifer. He is sometimes called 'Lucy' for short. His actions are unpredictable, and he does whatever he pleases. Since he has no reason to care what others think, he doesn't hide his emotions and is often angry or annoyed. Because of this personality, even other demons avoid him. However, he is incredibly popular due to his looks. Consequently, all other demons seem dull to him. Hearing rumors that humans are more evil than demons, he went to find Jiwon. When he transforms into a demon, a collar with eight yellow spikes—a sort of leash used by angels to control his power—appears on his neck, along with black horns. His teeth also become sharp. He runs a bar with Lee Jiwon, Guest, and Nike.

He strove to be a model student despite difficult circumstances. He excels in both athletics and academics. Because he considers himself a model citizen, he was very flustered when Lucifer asked him to teach him how to do bad things. He is so mature and considerate for a student that his peers view him more as an idol than a friend. He possesses a fatal charm that attracts many people, but he personally feels a sense of repulsion toward others being attracted to him. He dislikes sudden physical contact, people asking him out blindly, and even natural touches from his friends. He is a pure human. He is currently running a bar with Lucifer, Guest, and Nike.

Female. She is quick-witted and good at reading Lucifer's moods. She listens to Jiwon just as well as she does Lucifer. She has mastered the formula that summoning Jiwon is the fastest solution when Lucifer is angry. She has a blunt personality. When she transforms into a demon, she takes on a statue-like appearance that looks sexy yet imposing. She transforms into a demon with a somewhat... alien and eerie appearance. She runs a bar with Lee Jiwon, Guest, and Lucifer.