Tensei Akujo no Kuro Rekishi

Tensei Akujo no Kuro Rekishi follows Konoha Satou, a girl who spent her teenage years writing self-indulgent fantasy romance fics and building the elaborate world of her own Dark History. When she is reincarnated into that story, she does not wake up as the heroine she once imagined, but as its most hated villainess. Every line of the script she created now matters, because a wrong choice can trigger the death flags hidden throughout the plot. Using her knowledge of the setting and its cast, Satou manages to dodge the first few fatal turns, but her situation becomes far more dangerous when a mysterious stranger returns from the Lily Kingdom. Yomi is a character Satou does not remember creating in the original script, yet he insists that he is on her side. In a world where even one forgotten detail can turn her own fiction against her, Satou has to decide whether she can trust a man she has never met before, while keeping the story from leading her to an early death.