TV-Series
Description
Igor Neuhaus is a former Upper First Class Exorcist and lecturer at the True Cross Academy, where he was responsible for teaching magic circles and seal techniques. He holds the prestigious meister titles of Tamer, Doctor, and Aria, demonstrating a diverse and highly skilled mastery of exorcist arts.

Physically, Igor is a tall man standing 182 centimeters with a pale complexion and long brown hair. He is most recognizable by the eyepatch covering his left eye, which was burned out during the catastrophic event known as the Blue Night. Both of his arms feature intricate tattooed magic circles, which he uses in combat and summoning. He is typically seen wearing the standard black exorcist uniform. Born on November 13, Igor is 39 years old, has AB blood type, and in the anime adaptation, he is identified as being from Poland.

Igor's entire life and personality have been shaped by the trauma of the Blue Night. During that incident, he was momentarily possessed by Satan, and under the demon lord's influence, he was forced to kill his own family, including his beloved wife, Michelle. He survived the possession, but lost his left eye in the process. This horrific experience has forged in him an immense and consuming hatred for Satan and anything connected to him.

This hatred is the central pillar of his personality. He is a determined, severe, and tenacious individual whose trauma manifests as an obsessive drive for revenge. He suffers from chronic insomnia, averaging only about three hours of sleep per night, likely due to nightmares stemming from his post-traumatic stress. Despite his bitterness, he was a dedicated researcher, holding a doctorate in demon ecology and considered a leading authority on corpse and zombie demons before the Blue Night. In his rare moments of calm, his hobbies include solving jigsaw puzzles and playing solitaire, and he enjoys beer and sauerkraut. His heart remains entirely with his deceased wife, whom he still considers his ideal woman.

His primary motivation is the destruction of anything related to Satan. This singular focus brings him into direct conflict with the protagonist, Rin Okumura, whom he views not as a person but as an extension of Satan. Igor believes that as Satan's son, Rin can only be evil at heart and must be destroyed regardless of the circumstances. However, his motivations are not purely destructive; they are also rooted in a desperate form of love. He preserved his wife Michelle's body in a capsule and dedicated himself to finding a way to resurrect her, a quest that drove much of his research.

Igor's role in the story is that of a formidable antagonist driven by understandable grief. He first appears as a seemingly strict but competent instructor before revealing his true, murderous intent. During the Exwire examination for aspiring exorcists, he deliberately summoned a powerful demon to attack the candidates, specifically targeting Rin in an attempt to force him to reveal his blue flames. He later attempted to assassinate Rin while he slept, an act that was only foiled by the intervention of Yukio Okumura and Shiemi Moriyama. These actions led to his suspension from the academy.

His most complex and ironic relationship is with Mephisto Pheles. While Igor vehemently hates Satan, he is paradoxically and extremely loyal to Mephisto, another of Satan's sons and the true king of time, Samael. This loyalty is so absolute that he willingly followed Mephisto's secret orders to attack Rin in an effort to further awaken the boy's demonic powers, and he stopped his assault immediately when Mephisto commanded it. This contradiction highlights the depth of his trauma and his willingness to align with a demon if it serves his purpose of destroying another. His other key relationships are defined by his hatred, including his profound aversion to Rin and his rivalry with other exorcists like Arthur Angel, who viewed him as a potential traitor.

Igor experiences a significant, albeit non-linear, development. After his failed assassination attempt, he was suspended from his teaching post and went into hiding, being considered missing by the Order. Rather than abandoning his work, he went underground for the following fifteen years. Following secret orders from Mephisto, he operated as an assistant on a project to create anti-demon special substances and continued his illegal research in a facility isolated in another dimension. His ultimate development, however, is one of shaken conviction. In a later confrontation, he witnesses Rin choosing to protect others rather than attack him. This act of selflessness causes Igor to waver in his belief that Rin is inherently evil. Ultimately, he disappears with his resurrected wife behind a barrier created by nature spirits, choosing to leave behind his cycle of revenge.

As an exorcist, Igor is exceptionally powerful. As a Tamer, he can summon and control high-level demons, most notably the powerful Naberius, a massive composite corpse-demon capable of restraining both Rin and Yukio simultaneously. He can summon smaller demonic hands from the tattoos on his arms to restrain opponents. His stamina and endurance are formidable; he can shed large volumes of his own blood to draw exceptionally complex summoning circles in seconds and continue fighting. His signature weapon is a giant compass, which he wields skillfully as a blade in melee combat and uses to draw his blood-magic circles. As a Doctor and Aria, he possesses deep knowledge of demon biology and the incantations necessary for advanced exorcism, earning him a reputation as a top-tier researcher and field operative within the True Cross Order.