Transmigrating into a Book to Become the Demon Lord Heroine's Junior Sister

(Two female leads + slightly slow burn + bad ending + System + both leads are each other’s one and only + fake death)

Cute secret-identity junior sister × once-brilliant, cool senior sister

Su Yue transmigrates into a female-led novel. As a transmigrator, her mission is to save the heroine in the early part of the story and form a deep bond with her…

Just as she successfully wins the heroine over, returns to her original world, and is about to embrace her new life

“Nuo’er, how could you leave me behind and go on alone?”

Su Nuo looks horrified. “Why are you here?!”

“Of course I came here to find you, Nuo’er.”