Rin Okumura

The fifteen-year-old protagonist of the story, Rin is the son of Satan born from a human woman and is the inheritor of Satan's powers. His powers were sealed at birth into the demon-slaying blade Kurikara by Mephisto Pheles the True Cross Academy principal, allowing him to live a normal human life for about 15 years. Rin became aware of his true identity after Kurikara could no longer seal the blue flames he inherited from Satan, setting off a chain of events that led to the death of Shiro at the hands of Satan, who attempted to drag Rin back to the demon realm, Gehenna. Mephisto Pheles confronted Rin after Shiro's funeral with several exorcists, giving Rin the option to kill them all or die. Rin instead demanded to become an exorcist, an idea that amused Mephisto. Rin was then enrolled personally by Mephisto into the True Cross Academy, where he has since been pursuing his goal to become a Paladin and to defeat Satan. He is currently an Exwire and attempting to gain the title of Meister as a "Knight".
Rin can access the power he has inherited from Satan through drawing Kurikara. The sheath acts as a portal to Gehenna, which, when the blade is drawn, returns Rin to his demon form. While in his human form, Rin exhibits a number of physical traits that are signs of his demonic nature, such as sharp canines, slightly pointed ears, and a black, fur-tufted tail (which he keeps hidden in his shirt). In his demon form, Rin gains two horns as blue flames that float above his head, long elf-like ears, and his pupils turn red while his irides remain bright blue. In both forms, Rin can control incredibly destructive bright blue flames, the trademark sign of anything related to Satan. However, when he draws Kurikara, the magnitude of the flames dramatically increases and often leads to Rin being "consumed" by his own flames and losing his mind. Rin also has a Cat Sith, Kuro, who was initially Shiro's, as his familiar. Rin has been shown to have a talent for cooking, notably due to the fact that he had started cooking at the young age of 6.

Yukio Okumura

Rin's younger twin brother. When it was discovered that the woman impregnated by Satan was going to have twins, it was believed that Satan's powers would be split between them. Due to the weakness of Yukio's body, however, he did not inherit any of Satan's powers, thus being born fully human with the full extent of Satan's powers going to Rin. Yukio did, however, receive a spirit wound at birth from his brother, which allowed him to be aware of demons for as long as he can remember. Yukio secretly trained to become an Exorcist from the age of seven in order to protect Rin (through the help of Fujimoto). While both Yukio and Rin are in their first year at True Cross Academy, Yukio is already an instructor at the Exorcist cram school teaching Anti-Demon Pharmacology to Rin's class.
It is often stated that Yukio is a moreion, having already acquired the title "Meister" in both the Dragoon and Doctor class, while ordinarily most people would aim for Meister in only one class (both are still fully qualified exorcists). He is currently ranked a Middle First class exorcist. Even though he and Rin argue a lot, Yukio truly cares about his brother. Fearing Rin will be consumed by his demonic nature, Yukio often berates him for his impulsive actions and reckless attitude.
Later on in the anime, he becomes a demon just like his brother although this was not mentioned in the manga itself.




Mephisto Pheles (メフィスト・フェレス Mefisuto Feresu?)

Mephisto is the Chairman of True Cross Academy's Japanese branch. He is portrayed as a man with more money than sense but is very cheap when it comes to spending on others. After Fujimoto's death, he was ordered to kill Rin but instead accepted Rin's proposal of becoming an Exorcist and enrolled him into True Cross Academy. Mephisto is a powerful exorcist (holds a Meister in Honorary Knight, was able to subdue Amaimon while holding a berserk Rin off) and claims that he desires to "bring peace to both Assiah and Gehenna". Despite having served the True Cross for at least two centuries, elements of the Order still consider him suspicious.
It is known throughout the series that Mephisto is the son of Satan along with his brother, the Earth King, Amaimon and in episode 5, he referred to Rin as his little brother. He possesses the unique and peculiar ability of transforming into a small dog and conjure a giant cuckoo clock and other, which could imply that his abilities are Sorcery. He goes by the name Johann Faust the Fifth in public, a further pun on the play Faust. Also, his name is very similar to Mephistopheles.




Ryuji Suguro (勝呂 竜士 Suguro Ryūji?)

Ryuji (nicknamed "Bon") is a stubborn and hot-tempered individual. Despite his delinquent appearance (blonde streak in his naturally black hair, piercings) and attitude, he is very hardworking and the best student in class. Ryuji is the heir to the Cursed Temple in Kyoto. Because of the destruction of the temple in the Blue Night and his anger towards his father Tatsuma Suguro, he swears he will defeat Satan (a goal he claims Rin stole from him) and rebuild his Temple. When Rin's identity was revealed, he refused to speak with him at all. After a confrontation with his father and Rin, Ryuji and his classmates helped Rin escape impending execution and he reconciled with him, claiming that he only blames Rin for not trusting his friends with his secret. Ryuji is currently an Exwire, and trying to achieve Meister in both Aria and Dragoon.




Shiemi Moriyama (杜山 しえみ Moriyama Shiemi?)

Shiemi is the daughter of the woman who runs an Exorcist-only shop. She is kind and has an abiding love of gardening, but often lacks confidence in herself. She has blonde, short hair. Before the series, Shiemi never went out of her home and tended to the garden with her grandmother. After her grandmother died, Rin and Yukio exorcised the demon that was leeching her life force and she decided to become an Exorcist.
Shiemi is close to Yukio and Rin, and on amicable terms with Ryuji, Konekomaru, and Renzo. She was devastated when she discovered Rin and Yukio hid that they were sons of Satan, taking it to mean that she was not trustworthy. However on the Kyoto mission, she reconciled with Rin when he was imprisoned and joined with his other friends to help him escape. She is also friends with Izumo despite how Izumo initially used her. Shiemi has the talent to become a Tamer and can summon a reliable Greenman spirit that can produce healing herbs and barriers. She is currently an Exwire.




Izumo Kamiki (神木 出雲 Kamiki Izumo?)

Izumo is easily one of the best students and she's aware of it. She has a tsundere attitude and is offensive towards everyone except her childhood friend Noriko Park, a Korean living in Japan, who was the only one in her elementary school who would talk to her. Izumo has black hair, usually in 2 ponytails and very short eyebrows. Very prideful and often difficult to talk to, Izumo does care about her fellow Exwires and was the first of Rin's classmates to accept Rin after his identity as Satan's son was revealed. Izumo's reason for becoming an exorcist is still unknown, but connected to an incident that happened when she was a child. Izumo is attempting to achieve a Meister in Tamer, and can summon two Byakko (foxes) to fight for her.




Konekomaru Miwa (三輪 子猫丸 Miwa Konekomaru?)

Konekomaru is a timid but brilliant individual, able to come up with complex strategies in a short window of time. He is very loyal to Ryuji and Renzo, since they grew up together at the same Temple in Kyoto. He is bald and wears glasses. He is kind to everyone and the last to reconcile with Rin after discovering Rin's identity as Satan's son, seeing Rin's true good intentions. He is an orphan and the surviving head of the Miwa family. He plans to achieve the Meister in Aria.




Renzo Shima (志摩 廉造 Shima Renzō?)

Renzo is a very carefree yet fearful character. He's very loyal to Bon and Konekomaru, since both grew up with him at the Cursed Temple in Kyoto. Renzo is the second of the cast who accepts Rin after discovering his identity, finding ignoring Rin to be troublesome. He is infatuated with Izumo, obsessed with women but afraid of bugs. In elementary school, he was referred to as the "Erotic Demon". Now that he is in high-school, he is trying to be more refined. His hair is naturally black, but he dyed it pink (to the chagrin of his father). Renzo carries a K'rik (Khakkhara) staff to fight like his two brothers and plans to achieve the Meister in Aria.




Shura Kirigakure (霧隠 シュラ Kirigakure Shura?)

Shura is an Upper First Class Exorcist and Rin's mentor. She trained under the guidance of Fujimoto to obtain the title "Meister" in Knight and can draw a demon sword from a symbol above her chest when she states, "Devour the Eight Princesses, slay the Serpent". Her sword skills allow her to fight on par with upper level demons like Amaimon. Frequently chipper and obnoxious, Shura is carefree about her job, as she drinks alcohol in excess and oversleeps. She appears to harbor a dark past, as she claimed Shiro "came and rescued" her.
Disguised under a hood as Yamada, one of Rin's classmates, Shura revealed herself when Amaimon attacked Rin, saving Rin from Amaimon's attack before taking him into custody. A Senior Inspector, Shura had orders to investigate the Japanese Branch and eliminate anything she discovered related to Satan. She also held a grudge against Shiro (who asked her to teach Rin how to use Koumaken) for "casting her aside". Shura intended to dispose of "her master's mess", Rin, after verifying that Rin was Satan's son, but Rin convinced her he would become a Paladin and prove Shiro was right to let him live.
Shura decided to teach Rin how to control his powers in accordance with Shiro's wishes, leading to a bond akin to an older sister-younger brother relationship between them. Yukio and Shura are also familiar with each other since Shiro trained both of them. Shura nicknamed Yukio "four-eyed chicken".