I Transmigrated Into a Book as a Spy Beside the Villain

Xuan Liuer wakes up to find that her whole world has turned upside down. Looking at the bed and the unfamiliar surroundings, she soon realizes she seems to have transmigrated into a book, and into the body of a disposable traitor at that. She thinks that having read the original story will at least help her keep the villain from finding out, but on an otherwise ordinary day, he suddenly corners her...