When one fateful search through the Everfree Forest leads Rarity to a secret library inhabited by the spirit of an ancient alicorn princess, she realises that it may be time to start believing in fairy tales.
As an ancient alicorn trapped inside a library, Princess Twilight spent many a century dreaming of being rescued from her prison. Now, finding herself in an entirely new Equestria, she realizes she'd never planned for somepony to actually succeed...
Rarity had always known she would have an arranged marriage—such was the life of a princess, after all. She just hadn't expected her wife to be a sphinx or that she would actively avoid her, and not just because she loves books.