Shuurei Kou, daughter of Kou Shouka—a Royal Archivist from the esteemed Kou clan—and Hyou Shoukun, the enigmatic Red Immortal, navigates life amid stark contrasts. Born to an immortal-human union once thought impossible, her miraculous existence hinges on her mother’s spirit sealed within her, stabilizing her fragile health while granting sporadic healing powers that erode her already shortened lifespan. Despite her noble heritage, her family languishes in poverty due to her father’s modest income and their altruism during a past imperial crisis. Forced into self-reliance early, she masters domestic skills and juggles diverse roles—teacher, erhu performer, brothel accountant—to sustain their household.

Driven by reformist zeal, she aspires to governance but faces systemic barriers as a woman. Undeterred, she accepts an unconventional proposition: mentoring Emperor Ryuuki as his temporary consort, leveraging the position’s financial incentives and political influence. Her tenacity transforms the apathetic monarch into a committed ruler, catalyzing his historic decision to admit women to imperial examinations. Achieving third-highest honors, she shatters norms as Saiunkoku’s first female official. Assigned to co-govern Sa Province, she confronts entrenched opposition, including Sa Sakujun’s coercive marriage bid, thwarted only by his self-sacrifice to protect her career. Later, as a Censorate member combating corruption, her idealism evolves into strategic resilience under mentors like Ki Kouki.

Loyalty defines her relationships. Ro Ensei, her steadfast assistant, remains her unwavering ally, while her bond with Ryuuki deepens into marriage despite her fears rooted in her mother’s tragic legacy. Their union ends in childbirth tragedy at thirty, leaving daughter Chouka and a grieving Ryuuki, who never remarries.

Optimistic yet pragmatic, she wields inherited traits—uncanny gambling luck and alcohol tolerance—as tools against adversity. Though her achievements redefine gender roles, she credits perseverance over innate talent, viewing herself as ordinary. Her legacy persists as a trailblazer who reshaped a nation’s destiny through resilience and reform.