Known as the "Earth King", he is supposedly the second son of Satan, and the younger brother of Mephisto.
Amaimon is the Earth King. (More information will come)
Amaimon is created by Kazue Kato and has no information regarding any inspiration used to create him. He first appears in Blue Exorcist volume 2 (Chapter 7) and episode 5. His Japanese actor is Tetsuya Kakihara.
He has two shades of green for his hair and the lighter shade is the first layer. Also, he has a pointed hair style.
He loves to fight and gets bored easily, and he hates to be ignored. A example of that is in episode 15 where he is choking Ryuji for ignoring him.
Amaimon first appears when he meets his brother, Mephisto, on a tall tower. He wonders why his father, Satan, and his brother are so interested in Rin. Later, he appears during the Cat Sidth incident as he and Mephisto watch Rin confronting Kuro from above the bridge in a room. When Mephisto asks Amaimon about Rin, he tells Mephisto that he is not impressed with Rin. Mephisto asks Amaimon if he wants to bring out Rin's true potential. Before Amaimon agrees, he informs his brother that he will tour Japan to learn about it.