From the back cover of the Ace first edition: "You can find the magic within. But sometimes, the magic finds you. For university librarian Emma Merrigan, the world has provided a comfortable routine. Her job. Her quiet apartment. Her life. Nothing much changes and that's fine with her. But that was before Emma took in a terrified young girl hiding in the library. And the nightmares of her childhood returned. And the untapped powers passed down by her long-dead mother were awakened. Now, her life is about to become anything but routine..."
Source · ISFDB CC BY 4.0