For centuries, the Arid Dominion has been ruled by queens with magical powers. And they are always under threat of kidnapping by the ruler of Tyndra, the evil, deceitful and immortal King Eidolon, who has power over the shadows. That's why the queens of Arida jealously keep secret the fact that a generation later they are giving birth to twin heiresses, one of whom must replace her sister if she disappears or dies.Meren, or Mereneita Evangeline XII, is ready to give her life for her sister, Tabra Jutheria I. Accustomed to living as a commoner, she is trained to slip into the palace and play the role of a princess when necessary. So, when the girls' grandmother, the current queen, dies and Tabra is to take the throne, Meren prepares to fulfil her destiny - to replace her sister on the eve of the coronation. However, she is kidnapped by the mysterious Shadow Ghost, who seeks to use the princess's magic, unaware that he has kidnapped the wrong one...