Mephisto Pheles

Mephisto Pheles is a characters from the Ao no Exorcist anime and manga.

Mephisto, real name is Samael, is an Exorcist and the second strongest of the Eight Demon Kings; he holds the title The King of Time. He uses the name Johann Faust V (Yohan Fausuto Gosei) in public and is the Principal of True Cross Academy. Following the death of Shiro Fujimoto, Mephisto takes it upon himself to enroll Rin in True Cross Academy.

Appearance
Mephisto has dark purple hair and forest green eyes. He is also very tall, having a height of 195 cm (6'5").  He is usually seen in an elegant white outfit that consists of a white top hat with pink and purple around the base, purple gloves, a tie that is pink with white dots, a white suit-shirt and undershirt, jester-style pants, and pointed shoes. His appearance prompts Rin to refer to him as The Clown. As the series progresses, he stops wearing the jester pants and pointed shoes, instead wearing white dress pants and black shoes.

In addition, he can transform into a small white dog when he counts down from three in German (up to three in the anime). In this form he is a small, fluffy, Scottish terrier-looking dog with a large pink ribbon around his neck with a silver trinket attached to it, the trinket being the symbol of an Exorcist. He also is shown to be able to transform into a Bug.

Personality
Shrouded in mystery, one quickly learns of Mephisto's innate ability to act as if he knows more than what he is letting on. Careful and meticulous, he is like a chess player, always ahead of the game.

He enjoys chaos, as he stated to himself that he was a hell-raiser, and Assiah to be his playground. He frequently observes the growing conflict around Rin and his friends with delight, though he does not wish to see any of his students get killed. He apparently 'loves' humans. When Mephisto first meets Amaimon in the series, it is implied he is conspiring with Satan and is most likely training Rin on his orders. He likes to make gambles with whoever possible, including Fujimoto, Rin, and the True Cross Order.

He is prone to eccentric moments nestled in between serious moments, making light of a heavy mood and is portrayed as a man with more money than sense, but is very cheap when it comes to spending on others. Like his brother, he loves to eat sweets and he is deeply interested in the Japanese pop culture, proudly stating that he is an otaku (that is, loves computers, anime/manga, and/or pop culture to the point that it negatively affects his social life).

Abilities
Mephisto is powerful enough to block any higher ranking Demon from entering into the academy. It is stated when Pheles told Amaimon the King of Earth, to enter into the academy, Amaimon replied that he can't enter into the academy without the "Infinity Key" because of Pheles' barrier. How powerful he is has not been shown yet but he has mentioned that he is an Honorary Knight, the position two ranks below Paladin. When he sealed Rin's blue flames into Kōmaken, he only had to snap his fingers.

Transformation: Mephisto possesses the unique and peculiar ability of transforming into a small dog after counting down from three in German. This form allows him to escape through small gaps and spaces. He has also shown the ability to transform into a cockroach, which he uses to spy on a conversation between Yukio and Shura.

Time-Space Manipulation: As the King of Time, Mephisto has dominion over time and space, manipulating it in various ways. He is able to transfer his and others' consciousness into other dimensions, such as Gehenna. Also, he has shown to be able to stop time for an unknown period of time allowing him to snatch Rin's sword. Summoning: Mephisto is able to summon a variety of objects by counting up to 3 in German. Flaming Pentagram: When the Boys' Dorm was attacked by the masked person, Mephisto said that he was going to make the person regret attacking the academy. He waves his umbrella in circles above him and a giant flaming pentacle appears in the air. It creates lightning as it hovers. It, like his other abilities, appears to be activated by him counting to three in German. However, Arthur Angel puts out the symbol with water, so it is currently unknown what it would have done were it to have been used. (Unnamed)
 * Er Stopfen (Erusutofuven): A barrier that stops time from passing within it, it lasts about four to five months.
 * Kuchens Kuckucksuhr (Kūhenzu Kukkusuwā; Ger: "Cake Cuckoo Clock"): A giant candy clock, it has a large cuckoo which springs out and grabs the target. It is first used to capture Amaimon.
 * Das Stärkste Gefängnis ( Dasu Shutarukusute Gefengunisu; Ger: "The Strongest Prison"): A prison touted as the "strongest defense," it has the ability to halt the movements of those who approach it with hostile intent. It cannot be opened from the inside without the key but can be easily opened from the outside. It is first used to imprison Rin.

Telekinesis: Mephisto show the ability to freely move objects he summons, such as making his chair levitate, flying a rice cup in the air, and more.

Trivia

 * Both his name and alias, Faust, are taken from German literature called Goethe's Faust in which the main character, Faust, wagers his soul with Satan.
 * Furthermore, the Demon Mephistopheles in Goethe's Faust is able to transform into a small dog too.
 * He also shares his birthday with Johann Wolfgang von Goethe
 * Mephistopheles in Goethe's Faust is the manifestation of contradiction. In Ao no Exorcist, this is featured by him praising the value of high quality food in the school cafeteria, while he is cooking instant noodles, him wearing a unique white attire, while the students wear black uniforms and of course, him being a demon leading the True Cross Academy.
 * His real name, Samael, is an archangel in Talmudic lore who fell from heaven, and is also called an angel of death.
 * In Judaism lore, Samael is the guardian angel of the Biblical character Esau, brother of Jacob. In some theories, the angel that Jacob wrestles (from whom he earns the name Isreal) is named Samael.
 * His average hours of sleep is 1 hour.
 * He is pretty good at party games, claw crane games and chess.
 * His pastimes and talents are: watching movies, reading manga, watching anime, playing video games, listening to music, toys, and subcultures.
 * All manga genres are his favorites.
 * His favorite food is junk food (mostly candy).
 * His favorite type of women are those who are temptresses, "devilish", or elegant/beautiful. In the Weekend Hero novel, he mentions also fancying "pretty girls with a sad past", as well as charismatic women.
 * He has a frequent tendency of breaking the fourth wall by directly speaking to the reader.
 * He likes to make gambles with whoever possible, including Fujimoto, Rin, and the True Cross Order.