Pheles is the Chairman of True Cross Academy and also an Exorcist. After Fujimoto's
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Mephisto Pheles in episode 3

death Pheles was ordered to kill Rin, however he accepted Rin's proposal in becoming an Exorcist and allowed him to enroll in True Cross Academy. It has been suggested that he, like Rin is a son of Satan. He possesses the unique ability to transform into a small dog resembling a white scottish terrier after counting to three in german and snapping his fingers. His power and fighting prowess have not yet been shown but he has achieved the rank of honorary knight. He is seen as careless as a result of his actions. For instance, allowing several higher grade demons onto campus. He is portrayed as a man with more money than sense but is quite miserly when it comes to others.His name is an obvious pun on the word Mephistopheles, which is the name for the infamous demon of Faustian lore.