Keiki, also known by the title Taiho, is a kirin and the Saiho, or sacred protector, of the Kingdom of Kei. A kirin is a divine, chimerical creature whose sacred duty is to select the ruler of a kingdom according to the will of Heaven. Keiki was once the chosen kirin of a previous ruler of Kei, a woman named Jokaku. Her reign, lasting only six years, was a disaster; she became irrationally jealous and tyrannical, enacting cruel laws and executions. Her unworthiness caused Keiki to contract a fatal illness known as shitsudou, which afflicts a kirin bound to an unrighteous monarch. To save his life, Jokaku abdicated the throne and subsequently died, and she was posthumously known as Yo-ou, the Prophet. Cured by her abdication, Keiki immediately began his sacred search for a new ruler.

Keiki’s personality is defined by a stark contrast between his outward demeanor and his inner nature. On the surface, he appears to be quiet, stoic, and unemotional, often coming across as cold, distant, or even gruff and unapproachable. He rarely displays overt emotion and speaks with formal precision, which can make his words seem harsh or tactless even when that is not his intention. This emotional reserve is a direct result of his traumatic past; his close relationship with the previous empress ended in catastrophe, leading to his illness and her death, and he now hides his feelings behind a mask of coldness out of a deep sense of guilt and fear of repeating his mistakes.

Beneath this stoic exterior, however, Keiki is a deeply sincere and caring individual. He is intensely loyal to his duty and to the people he is sworn to serve. Like all kirin, he abhors violence and war, always preferring peaceful resolutions to conflict. This caring quality is most visibly directed toward other kirin, particularly the young Taiki of Tai, towards whom he shows a rare softness and protectiveness. He is also genuinely dedicated to the welfare of his chosen monarch, Youko Nakajima, and his actions are consistently aimed at ensuring her success and safety.

Keiki’s primary motivation is the fulfillment of his sacred duty to the Kingdom of Kei. He is driven to find and serve a worthy ruler to restore stability and peace to the kingdom, a goal made all the more urgent by the failure of his previous choice. His personal experiences have left him deeply cautious and hesitant, and his initial confidence in Youko is fragile, as he worries constantly about her inexperience and ability to rule effectively. Yet, his sense of responsibility compels him to be a dedicated advisor and protector, even when he struggles to express his support directly. He is motivated by a desire for order and to never again see a ruler fall into the kind of ruin that Jokaku did.

In the story, Keiki serves as the catalyst and a central figure. He is the one who finds Youko Nakajima, who is living as a taika, or a child born outside the Twelve Kingdoms, in Japan, and forcibly brings her back to the world of the Twelve Kingdoms to be the new ruler of Kei. However, they are separated upon arrival. Keiki is quickly captured and placed under a magical enchantment by Kourin, the kirin of the neighboring Kingdom of Kou. This spell renders him unable to speak, summon his shirei (spiritual familiars), or return to his human form. He is forced to appear as a prisoner before the false queen Joyei, Jokaku’s sister who has usurped the throne of Kei, giving a false legitimacy to her rule. He remains captive for a significant portion of Youko’s early struggles until she, with the aid of the King of En, successfully storms the palace, rescues him, and frees him from his enchantment. After Youko officially ascends the throne of Kei, Keiki resumes his role as her Saiho, advising her on statecraft, politics, and governance as one of her most crucial and trusted allies.

Keiki’s most important relationship is, of course, with Youko Nakajima, the queen he chose. Their relationship evolves considerably. It begins with Keiki’s forceful abduction of her, and his subsequent capture leaves her to fend for herself, creating a relationship fraught with difficulty and mistrust. He is initially plagued by doubts about her abilities, haunted by the failure of his previous ruler, and serves as a stern and sometimes exasperating mentor. He frequently sighs in frustration at her stubbornness but remains committed to her success. Over time, as Youko grows into a powerful and wise leader, Keiki develops a genuine and profound respect for her, seeing that she is nothing like her predecessor. His loyalty becomes absolute and sincere, even if he still struggles to express his emotions openly. He shows his concern through his protective actions and his dedication to helping her learn everything she needs to know to rule Kei well.

Another key relationship is with Taiki, the young kirin of Tai. Keiki is notably warmer and more openly caring towards Taiki than he is with almost anyone else. He serves as a mentor and a source of comfort for the confused and overwhelmed young kirin, and their bond is a significant one. It is through his interactions with the gentle and kind Taiki that Keiki begins to learn how to let people into his own cold emotional shell. He is also highly protective of Taiki, showing a personal concern that transcends his official duties. Keiki shares a long-standing and respectful relationship with the King of En, Shouryuu, recognizing him as a wise and capable ruler. He also has a history with Kourin, the kirin of Kou, who betrayed and enchanted him, though he does not seem to harbor a personal grudge, understanding that she was compelled to follow her own ruler’s will.

Keiki undergoes a subtle but significant personal development. While he does not undergo a dramatic personality shift, he gradually opens up. Forced by his past trauma into a state of emotional numbness, his interactions with Youko and his bond with Taiki help him to become more serene and to show his caring qualities more readily, even if he remains reserved. He learns to trust in Youko’s strength and grow more confident in her leadership, transitioning from a doubtful and cautious advisor to a sincerely loyal and respectful servant. His arc is one of learning to overcome the trauma of his past failure and re-engaging with his duty in a healthier, more trusting manner.

As a kirin, Keiki possesses several notable supernatural abilities. He has two primary forms: his human form, in which he appears as a tall, elegant man with long, pale gold hair and violet eyes, and his true kirin form, that of a majestic, golden-scaled, unicorn-like creature with a flowing mane and graceful antlers. He can summon shirei, which are spiritual familiars that serve him, though his enchantment at the hands of Kourin temporarily stripped him of this power. As a kirin, he is also instinctively repulsed by violence and bloodshed. Furthermore, he serves as the province lord, or governor, of the capital province of Kei, which gives him command over the Provincial Guard and makes him a very hands-on political figure, actively involved in the governance of the kingdom.