Kou Houju, primarily known as Kou Kijin, holds the position of Minister of Revenue. His original personal name remains obscure; "Kijin," meaning "weirdo," became his official name after he adopted it. This change followed a pivotal personal event stemming from his unrequited feelings for Kou Yuri.

He possesses extraordinary beauty, a trait causing him distress rather than pride. In his youth, his appearance caused mass distraction during the imperial examinations, an incident dubbed "The Nightmare Exam." His presence resulted in only two other candidates passing alongside him, while thirty officials were dismissed for losing focus. This outcome deeply troubled him, as he believed his high score resulted from unfair distraction, not merit.

To conceal his face, he wears various masks covering his entire features, frequently featuring a movable lower panel for eating or drinking; these masks also alter his voice. Many masks are crafted by his close friend Kou Reishin, reinforcing his eccentric reputation. Though often assumed to hide deformity, their true purpose is preventing the overwhelming reactions his beauty provokes—instances include causing officials to faint or become hysterical. His hair remains unbound, defying customary styles.

His relationship with Kou Yuri profoundly impacted his life. She served as a maid for Reishin and was unaffected by his appearance, sparking his interest. Learning she felt adrift without Reishin, he proposed marriage to offer her protection within the Kou clan. However, Yuri seemingly rejected him with the message that she "can’t stand beside someone with a face like yours." Unbeknownst to him, Reishin intercepted and altered this message due to his own feelings for Yuri. Upon Reishin's marriage to Yuri, a devastated Houju legally changed his name to Kijin and began wearing masks permanently—a practice formally sanctioned thereafter.

Professionally, he is a strict and efficient Minister of Revenue. He maintains an air of mystery, amplified by his masks and reserved nature. Despite this, he demonstrates kindness to Kou Shuurei, Reishin’s niece, when she works under him disguised as a man. He recognizes her true identity but keeps it confidential. He comforts her during thunderstorms, aware of her fear, and brings her flowers when she is ill. He also teases Reishin by suggesting an interest in marrying Shuurei, provoking strong reactions from his friend.

His backstory includes deep bonds formed with Reishin and Tei Yuushun while preparing for the imperial exams. When Yuushun was assigned to the volatile Sa Province, Kijin persuaded Reishin to remain in office to facilitate their eventual reunion in the capital. This trio’s friendship remains a cornerstone of his personal life.

In a pivotal display of authority during Reishin’s trial for malfeasance, he removes his mask to confront a corrupt official. The act causes the official to nearly lose his sanity, while other court members who fail to shield themselves faint or become hysterical. This moment starkly demonstrates the power of his unmasked presence and his willingness to wield it for justice.