Asmodeus or Asmodai is a king of demons mostly known from the deuterocanonical Book of Tobit. The demon is also mentioned in some Talmudic legends, for instance, in the story of the construction of the Temple of Solomon. He was supposed by some Renaissance Christians to be the King of the Nine Hells. Asmodeus also is referred to as one of the seven princes of hell. In Binsfeld's classification of demons, each one of these princes represents one of the seven deadly sins (Pride, Lust, Envy, Sloth, Greed, Gluttony, and Wrath). Asmodeus is the demon of lust and is therefore responsible for twisting people's sexual desires. It is said that people who fall to Asmodeus' ways will be sentenced to an eternity in the second level of hell.
The 32nd spirit of the Goetia, he is a great king, strong and powerful. He appears with three heads, the first like a bull, the second like a man, and the third like a ram. He also appears with a serpent's tail, belching or breathing fire out of his mouth and his feet are webbed like a goose. He sits on an infernal dragon carrying a lance and flag in his hands. He is first and foremost under the power of Amaymon and when summoned the summoner must be standing with his cap off, for if it is on he will deceive them and reveal all of their doings to others. He teaches the art of arithmetic, geometry, astronomy, and other handicrafts. He also gives full and true answers to your commands and can render a man invisible, along with showing the place where treasures lie. He governs 72 legions of inferior spirits. - The Lesser Key of Solomon.
His form as an Angel is Asmodel, the Angel of April and Patience who rules the Zodiacal sign of Taurus.
The guardian of the last prisoner in a birdcage at Kagome Tower. He tells them to leave for if the prisoner were to be freed or remember his name doom will fall upon the world. He states he will spare them if they leave, but laughs when they do not. He proclaims he will kill Flynn and take Isabeau as his bride and simply shatters upon defeat.