Transmigrated: I Became an Envoy of the Heavenly Dao

【Transmigrate into a book + Reborn + No romance + System】 A novel called The Tale of Yao Xian is currently being serialized to great acclaim. But as the heroine's character goes increasingly off the rails, readers unite to condemn the author, Xingxiangzi. Faced with an overwhelming flood of criticism, the author feels as if she has fallen into an abyss. When I open my eyes, the System tells me to transmigrate into the book and fix the story that's gone off the rails. Xingxiangzi: You got it! Sleeves up, let's get to work! Struck by lightning! Xingxiangzi: I can take it! Set on fire! Xingxiangzi: Still alive! Contract a super-tier demon beast! Xingxiangzi: The System is sending me a care package! Wipe out the demon clan! Xingxiangzi: Just destroy the world already! Realizing something is seriously wrong: “Hey! Isn't she supposed to be the protagonist? Why is everything falling on me?” “And why is the difficulty of leveling up shooting through the roof???” After struggling for a while... “Anyone who wants to be Heaven's emissary can have the job. I'm done!” I'm terrible at writing introductions, so please head straight to the story!