The story

You wake as an extra worth two lines of stage direction. Ninety days from now, at the Moon Banquet, your role is to be framed for poisoning and cut down by the crown prince's sword. If you cannot run, only one way is left. Stay at that dangerous man's side and snap the flags meant to kill you, one at a time.

You wake inside the romance-fantasy novel you were reading until last night. Not as the heroine, not as the villainess, but in the body of the nameless Maid A, the one who takes the blame in the chapter-three poisoning and exits by the crown prince's sword. Luckily, you read this book to the end. You know who the real poisoner is, in what order the frame-up gets assembled, and that the cold crown prince has in truth spent years baiting his own life to hook the one who killed his mother. Ninety days until the Moon Banquet. A maid's only ways to stay near a crown prince are the tea service and a scrubbing cloth, and that is enough. One teacup, one silver spoon, one line of gossip at a time, you will turn all of it over, tear chapter three out of the book, and write a chapter four of your own. The trouble is that the further you stray from the script, the more the eyes of a man who never once looked at a maid keep following you.

Knowing the script of your own death in advance. Which hands the poisoned cup passes through, which cot the vial is planted under, only a reader who finished the book can step on a flag early and put it out.
The moment the crown prince watches a maid hold a cup to the lamplight and dip the silver spoon first, and then stays to watch the whole service through. When a bit part starts speaking lines, the lead loses his place in the script.
The night of the Moon Banquet, the poisoned cup rising exactly as the book wrote it. The man who is supposed to draw his sword instead takes the maid's wrist and pulls her behind him. This scene is going somewhere the story you know never went.