After I Transmigrated into a Book, the Sickly Villain Turned Dark for Me

[Upright, Selfless, Kind-Hearted Heroine X Mad, Merciless, Dark Hero] [HE + Supporting Villainess + transmigrate into a book + Save the Villain + Regretful Pursuit] Nan Li, an overworked office worker, transmigrates into the role of a vicious supporting villainess. The System assigns her a mission: stop the villain, Xie Beichen, from becoming corrupted. Xie Beichen is short-tempered and utterly cold-blooded, so Nan Li goes to great lengths to win him over. She tutors him in the schoolroom at sunset, waits for him after class every day, and brings him delicious pastries. They take outings together by the River of the Beyond, release lanterns and watch fireworks during the Lantern Festival, and visit Jinyu Temple to pray for blessings... But once he learns what it means to love, he still resolutely goes down the same old path. The plot seems to have changed, and yet it seems unchanged. The day Nan Li dies, snow falls heavily, covering the world in white. She is tortured to death in the Forbidden Water Prison. As she falls into the water, countless images flash through her mind, yet in the end, all she remembers is one heartfelt word: “Ahan.” Nan Li smiles. She doesn't know if it's because the water is so cold, or because she feels she can finally be free. Six months later, when Xie Beichen learns of her death, he's consumed by rage and goes berserk, descending into darkness. The lives of all beings across the Six Realms are laid waste, and they tremble because of him. The immortals bring out their treasures and beg for mercy. Little do they know that amid all the chaos across the Six Realms, all he wants is her.