TV-Series
Description
Ki Tanmoku is the head of the powerful Tanmoku family of exorcists and holds the title of Youmeishi. His primary duties involve performing large-scale exorcisms to cleanse the earth of evil spirits and conveying the wishes of the living to the divine realm. He is a tall young man with medium-length white hair, with two long bangs framing his face, and grey eyes, bearing a striking resemblance to his ancestor Rakugetsu Tanmoku. His typical attire consists of a long black hoodie over a white button-up shirt and black tie, paired with black jeans and a blue-and-black striped scarf.

Ki is known for his stoic and emotionally distant personality, presenting himself as cold and indifferent to most people. This demeanor is largely a result of the heavy responsibility he carries as the family master, forcing him to appear mature and stern beyond his years. Despite this, he has a lethargic side and is often seen sleeping or eating when not performing his duties, a habit that can irritate those around him. While he is generally detached, he can also appear heartless, as demonstrated when he fired a long-serving family butler after the butler's son nearly killed his spirit shadow. His grandmother, the family matriarch known as Obaa-sama, is one of his few allies within the household and deeply cares for him.

Ki's motivations are deeply intertwined with his role and his bond with his spirit shadow, You Keika. He encountered Keika after witnessing his death in a traffic accident and offered him a spirit pact to prevent his soul from dissipating. While his public persona is reserved, Ki shows a remarkably caring and protective side exclusively to Keika. He has stated that Keika is the most precious person in his life and the only thing that is truly important to him. He goes to great lengths to ensure Keika's safety, giving him enchanted robes for protection, sacrificing his own life to save him, and even paying for his funeral. According to Ki, Keika is the only person who values him for who he is, not for his status or abilities, as he stayed with Ki even when he was weak.

Key relationships in Ki's life are often complicated. He has a pre-arranged fiancée named Shin Shiyou, but he remains aloof towards her, and her love for him is unrequited. His relationship with his half-brother and personal secretary, Jimei Tanmoku, is complex; while Jimei takes care of Ki effectively, he is reluctant to accept him as the Youmeishi. Similarly, he shares a negative outlook with his cousin, Jiun Tanmoku. A significant figure from his past is his former bodyguard, Shouken Shinryuu. Ki initially believed Shouken had betrayed him, but later discovered that Shouken had sacrificed himself to protect Ki. As a child, Ki relied heavily on Shouken and was advised by him to refrain from smiling too much to avoid being taken advantage of. Furthermore, a childhood encounter reveals that Keika once protected a young Ki from bullies, though Keika remains unaware of this connection, and Ki later tracked Keika down to send a thank-you letter.

Throughout the story, Ki's character develops significantly, primarily through his deepening bond with Keika. Their relationship evolves from a contractual obligation into a profound mutual devotion with strong romantic undertones. Ki has kissed Keika on the lips and performed rituals like kissing his soul ring to release his distance restrictions. In Season 2, Ki establishes a deeper soul-binding pact out of fear that Keika might become an evil spirit without an earthly tether, leading him to realize that he wishes for Keika to continue existing even after his own death.

Ki possesses immense spiritual power, which is so overwhelming that he must wear a special earring to control it. To maintain the purity required for his spiritual duties, he avoids eating meat and must prevent injuries, as his condition makes blood transfusions impossible. A childhood scratch from the Rakugetsu sword temporarily sealed part of his power, which was later restored when the sword was properly sheathed. He is proficient in martial arts and sword fighting, skills taught to him by his master, and is capable of specialized techniques such as using spherical orb magic and spirit-binding rings. He is also quick-witted and a fast problem-solver, as shown when he silenced his family's critics by simply giving the Rakugetsu sword to Keika to use as his own.