Roza, the daughter of the ruthless and influential Viscount Dolcia, is forced into a political marriage with Adrion, the heir of the impoverished Berkley earldom. Adrion, who was separated from his beloved fiancée Cecil due to his family's debts, resents the arrangement and on their wedding night cruelly tells Roza he has never seen someone so ugly and that she disgusts him. Roza, who only married to obey her father, feels no affection for Adrion. Her sole goal is to save money, officially divorce him, and escape her father's oppressive control to gain her own freedom. Determined to achieve this, she throws herself into reviving the failing Barkeley estate, managing the household, farming, cooking, and caring for her young nephew, all while secretly competing in swordsmanship tournaments as the masked champion known as the White Rose Knight.

As Roza displays remarkable competence in everything from childcare to sword fighting, Adrion slowly becomes drawn to her, realizing she is nothing like the scheming noblewoman he imagined. Meanwhile, Roza remains focused on her escape plan, brushing off his growing interest. The story expands into a larger political conspiracy when Roza's father, Lord Dolcia, is revealed to be the former Crown Prince August, who was framed for the murder of the previous king by his brother Heinrich. Having faked his death and taken on a new identity, Dolcia has been grooming Roza to one day retake the throne and become queen in order to correct the corruption of the current regime. Adrion, learning the truth, must find his place beside a woman whose destiny now involves reclaiming a kingdom. The central narrative arcs include Roza's battle against her father's control and her evolving relationship with Adrion, the revelation of the royal conspiracy and the true history of the kingdom, and the question of whether Roza will still choose divorce and independence or embrace a future with Adrion as queen.