The Book of Living Secrets by Madeleine Roux
Perfect for fans of The Hazel Wood, this genre-bending page-turner from New York Times bestselling author Madeleine Roux follows two girls who transport themselves into the world of their favorite book only to encounter the sinister alternate reality that awaits them.
No matter how different best friends Adelle and Connie are, one thing they've always had in common is their love of a little-known gothic romance novel called Moira. So when the girls are tempted by a mysterious man to enter the world of the book, they hardly suspect it will work. But suddenly they are in the world of Moira, living among characters they've obsessed about for years.
Except...all is not how they remembered it. The world has been turned upside down: The lavish balls and star-crossed love affairs are now interlaced with unspeakable horrors. The girls realize that something dark is lurking behind their foray into fiction-and they will have to rewrite their own arcs if they hope to escape this nightmare with their lives.