Mephisto Pheles is a prominent character in the anime and manga series 'Ao no Exorcist' (Blue Exorcist). He is the enigmatic chairman of True Cross Academy and one of the Eight Demon Kings, specifically the King of Time. Mephisto is known for his eccentric personality, flamboyant attire, and mysterious motives. While he often helps protagonist Rin Okumura, his true intentions remain ambiguous, making him a complex and intriguing figure who manipulates events from the shadows to serve his own enigmatic agenda.