The first three books in Meg Cabot's Abandon series.
Abandon: Last year, Pierce died - just for a moment. And when she was in the space between life and death, she met John: tall dark and terrifying, it's his job to usher souls from one realm to the next.
There's a fierce attraction between them, but Pierce knows that if she allows herself to fall for John she will be doomed to a life of shadows and loneliness in the underworld. But now things are getting dangerous for her, and her only hope is to do exactly what John says ...
Underworld: Pierce Oliviera isn't dead. Not this time. But she's been taken by John Hayden, Lord of the Underworld, to the place between heaven and hell where spirits gather before their final journey. John claims it's to protect her from the Furies, who are hell-bent on vengeance against him. But could he have other reasons for keeping Pierce close? When she learns that the people she loves are under threat from the Furies, can she convince John to release her to save them- or will the price he asks for her freedom be too high?
Awaken: Seventeen-year-old Pierce Oliviera knew that by accepting the undying love of John Hayden she'd be forced to live forever in the one place she's always dreaded most: the Underworld. The sacrifice seemed worth it, but now her happiness and safety in the realm are threatened. The Furies have discovered that John has broken one of their strictest rules and revived a dead soul. If the balance of life and death isn't restored, both the Underworld and Pierce's home on Earth will be wiped out by the Furies' wrath. Pierce has already cheated death once ... can she do it again?