Mephisto Pheles

Mephisto Pheles is a Devil from the Extra Demons and has been active since the time of the previous Four Great Satans.

Appearance
Mephisto Pheles is a middle-aged man with gelled hair, which is a mixture of red and blue. He has heterochromia; his left eye is blue, while the right is red. He also gives out a mysterious atmosphere similar to that of Ajuka Beelzebub.

Personality
Not much is known about his personality other than the fact that he believes in Liberalism, so he didn't get along with the previous Satans. He also wasn't interested in the Rating Game, so he didn't give that many orders to Tannin, and allows him to roam freely as he pleases.

History
In the past, Mephisto was known as the legendary Devil that formed a pact with the first Georg Faust. After forming a pact with Faust, he remained in the Human world even after Faust died and quickly rose to the top of the Magicians, becoming the director for the Magician Council. He has also reincarnated Tannin and a Longinus possessor as members of his peerage as well.

The Legend of Oppai Dragon and his Lively Companions
Mephisto Pheles appears briefly in Volume 14, contacting the Occult Research Club through a magic circle, and handing them the documents of the Magicians that the Gremory Team could make a pact with. He also informs the Occult Research Club on the discovery of fake Phoenix Tears which acts similarly to the genuine ones and tells Ravel to be careful as there is a high probability of her being targeted.

Trivia

 * Mephisto Pheles likes the current Four Great Satans compared to the previous ones.
 * Mephisto Pheles has met Rias' parents, grandparents, great-grandparents, and great-great-grandparents.
 * Mephisto Pheles is the oldest Devil introduced in the series.
 * In legends, Mephisto Pheles' name is considered as one word, Mephistopheles