The Reincarnated Villainess' Dark History

Story:

In her school years Konoha Satou wrote a story in the dark fantasy style about the Count's daughter Konoha Magnolia and the knights surrounding her. Going to high school, the girl gets into a fatal accident, after which she is reborn in her own story, but not in the main role, but in the body of her younger sister Yana Magnolia.