As it was the last wish of her bedridden father, Emilia, the eldest daughter of the Duke of Bradley, reluctantly accepts a political marriage with Matthias, the eldest son of the Border Count Karen. She made this promise to avoid causing confusion among the people after the lord's death. However, Matthias cannot attend the wedding ceremony as he must defend the national border.

As a result, Emilia marries Matthias's proxy and travels to Vanlogia, her husband's territory. Despite the unwanted marriage, Emilia serves as the lady of the house in her husband's absence. She actively advances reforms in the territory on behalf of her husband, and unexpectedly, these reforms succeed, giving her fulfilling days. But one day, her husband, whose face she doesn't even know, finally returns. He harbors an oath that Emilia never imagined... What will become of their relationship?