Seraphina Ainsworth is transmigrated into the Great Xuan Dynasty. She marries the comatose Lord Heir, Julian Wynn. Challenged by the Second House, she uses her modern financial knowledge to resolve conflicts and sort the Marquisate's accounts. She develops a relationship with Julian Wynn—who feigned his coma—moving from suspicion to deep love. Together, they quell the Crown Prince's rebellion, defend against enemies, and usher in peace. Seraphina transforms into the powerful Princess Regent.