Countess's daughter Catherine suddenly realizes that she has been reincarnated into the world of a novel she loved in her previous life.Unfortunately, she has become the villainess who destroys herself because of her jealousy. If she becomes engaged to Prince Leonardo, the hero of the original story, she will eventually meet a terrible fate and be executed!Determined to avoid this ending, Catherine desperately tries to prevent the engagement from happening.However, things take an unexpected turn when Leonardo falls in love with her at first sight and makes her his fiancée. Despite Catherine's continued efforts, his persistent advances and schemes cause all her engagement-breaking plans to fail.