The Perfect Plan for a Fairy-Tale Ending

Contrary to the traditional fairy tale, my story takes a different turn. Unlike the pitiable young girl in the story who was saved by a prince, I have been reincarnated as Marcia Blick, the villainous sister. My family's cruelty towards me is unbearable, and as a result, I must flee. However, I cannot abandon my sister, Larisa, and so I suggest that we escape together. "Larisa, we must search for the prince who will bring you true happiness. Hold on, why are you proposing to me, Prince? It is my sister, Larisa, who is your beloved and not me. She is the one who will bring you the perfect happy ending."