After Failing to Win Over the Male Lead, the Eunuch-in-Chief Steals Me Away

[Transmigrate into a book + black and white Systems that control planes of existence + male lead who switches effortlessly between an obsessive, possessive yandere and an clingy puppy-dog mode + gentle yet resolute female lead + romance + devoted couple] The heroine, Tan Li, is a professional transmigrator. Once she successfully completes ten transmigration missions, she can return to the real world, leave her sickly body behind, and live a healthy life. When she transmigrates into the ninth book, something goes wrong. Interference from the Black System turns her from the heroine into a supporting female character in that world. After she finally manages to bring the aloof male lead down from his pedestal, she's forced to hand him over to the so-called new heroine. After faking her death, Tan Li begins her tenth transmigration. The ongoing battle between the two Systems causes her to lose some of her memories. She forgets the deeply painful events of the previous book, and even the male lead's face. But the scholar male lead from the previous book doesn't follow the Black System's plot and fall for the new heroine. Instead, after seeing Meier's corpse, he completely turns evil and slaughters his way across the land, even having the new heroine torn apart by horses. He follows Meier into the tenth book Tan Li has entered and becomes the powerful Nine-Thousand-Year-Old. In the tenth book, the heroine has not only changed her appearance but also lost her memories of the male lead. How will he find her? And how will he begin the long road to winning her back?