"Your Highness, the 'Witch of Ruin' mentioned in the prophecy is me, your fiancée."

Duke's daughter Amalie remembers being reincarnated as a character from a novel she was reading, right after her engagement to Crown Prince Theodore. Amalie is destined to become the "Witch of Ruin" who brings calamity, consumed by jealous flames after the Saint steals Theodore from her. Amalie tries her best to escape her cursed fate in her own way, but destiny stands before her again and again. Cornered, Amalie finally tells Theodore that she is cursed as the Witch of Ruin. It's a bit darker and more extreme than usual, but ultimately has a happy ending (salvation).