Wen Liyu is a five-hundred-year-old koi spirit who failed her thunder tribulation and was rescued by the Director of the Quick Transmigration Bureau. For years, she lived in the Bureau's Wishing Pool, granting luck to agents before being drafted into active missions due to a surge in workload. During her first assignment, a transmission error leaves her trapped in the body of a small koi fish in ancient China. She is nearly boiled into soup for a concubine but escapes when a white cat snatches her and drops her near Chu Shaoyao, a sickly and despised prince living in the Cold Palace.
Chu Shaoyao, the emperor's first son, was once favored but was abandoned to the Cold Palace at age four after his mother died and his younger half-brother, Chu Shaohua, rose in status. Framed at sixteen, he was exiled to guard the imperial mausoleum, where he transformed into a ruthless tyrant who would eventually seize the throne and commit suicide. Wen Liyu’s mission is to survive, build affection with Chu Shaoyao, and bear his child to stabilize the world’s collapsing energy. The system assigns her daily tasks such as watering vegetables and mending clothes, rewarding her with points that can be used in a shop to buy transformation pills, healing medicines, and other items.
Wen Liyu uses a transformation pill to take human form and cares for the feverish prince, feeding him medicine and finding his lost jade pendant. She discovers a hidden crossbow trap set by his enemies and warns him, helping him avoid the assassination attempt. Her actions alter the original plot, earning her significant points and unlocking a higher-level shop. She learns that a transmigrator female lead is aligned with the antagonist, Chu Shaohua, and that her primary goal is to prevent Chu Shaoyao’s tragic fate.
As Wen Liyu spends more time with Chu Shaoyao, their relationship deepens. She uses invisibility cards to spy on the palace and warns him of a poisoning plot against Consort Wen, which he successfully counters. Chu Shaoyao, initially suspicious of her strange behavior, begins to trust her and relies on her insights. Wen Liyu’s bold and affectionate nature disarms his cold exterior, leading to intimate moments that blur the line between mission and genuine emotion.
The story follows Wen Liyu’s efforts to complete her missions while navigating the dangerous political landscape of the palace. She balances her duties as a koi spirit with her growing attachment to Chu Shaoyao, using her system-given abilities to protect him from various threats. As she earns more points and unlocks new capabilities, she prepares for the challenges ahead, knowing that her success is crucial not only for her own ascension to dragonhood but also for the survival of the world itself.
