Once every hundred years, an imperial election is held to avert a ruinous future. Numerous candidates for the throne make a pledge to the saint and compete for the throne. In this world, Silvia, the eldest daughter of the Holy Duchy of Bernia and a descendant of the first saint, is oppressed by both her family and the people of her territory because she was born without magical powers. On the night of the saint's birthday, when a new saint is supposed to be chosen, the holy eye awakens within Silvia, even though she should have no qualification to be a saint. Realizing that her family will treat her as an experimental subject now that she has manifested this power, she secretly flees her home. As she desperately runs for her life, she has a fateful encounter with a demon, who protects her from her pursuers and takes her into his care. This demon, planning to participate in the imperial election, forms a contract with Silvia, setting her on a path from being a disqualified saint to aiming for the strongest saint. The story follows her journey through the imperial election, her evolving relationship with the demon, her struggle against the family that abused her, and her quest to claim her own future in a world that had rejected her.