My Black Lotus Disciple Is Up to No Good

[Transmigrate into a book + master and disciple + villain + mutual salvation] Jiang Zhiyu transmigrates into a book, only to find herself in the role of the expendable villainous master! The ending is already set in stone: once the male supporting character turns evil, she'll be the first one he kills. To survive, she has no choice but to reform her bottomless black-hearted disciple. When people bully him, she stands up for him. When he wants revenge with his own hands, she teaches him to cultivate. When he wants to turn evil, she inspires him with positive energy... Then he wants to slaughter everyone in the world for her? Wait! Something's not right... The black-hearted disciple is still the same, except now he's a black lotus that blooms only for her.