Hollow Girl by Hillary Monahan
Bethan is the apprentice to a green healer named Drina in a clan of Welsh Romanies. Her life is happy and ordered – and modest, as required by Roma custom – except for one thing: the son of the chieftain has been secretly harassing her. One night, Silas and his friends brutally assault her and a half-Roma friend, Martyn. As empty and hopeless as she feels after the attack, she asks Drina to bring Martyn back from death’s door. “There’s always a price for this kind of magic,” Drina warns. They way to save him is gruesome. Bethan must collect grisly pieces to fuel the spell: an ear, some hair, an eye, a nose, and fingers. She gives the boys who assaulted her a chance to come forward and apologize. And when they don’t, she knows exactly where to collect her ingredients to save Martyn.