Songlight

"Elsa is used to hiding the most important parts of herself--her feelings for Rye, her distaste for a world ruled by men, and, most crucially, her gift of songlight. She buries that secret deep inside. In Brightland, those with songlight are called Unhumans and are abhorred. Rye is the only other person Elsa has known with songlight, and their shared bond has brought them together. Elsa's world begins to fall apart one desperate, heart-wrenching day and she doesn't know where to turn until a girl appears before her. But the girl isn't really there--her songlight has been drawn to Elsa's frantic grief. Elsa lives in a remote seaside village; Nightingale, her new friend, lives in a city hundreds of miles away with her father, a government official responsible for rooting out Unhumans. The two never expected to connect via songlight. But when they do, and when they realize the extent of their power, they'll be thrust in the middle of a war that threatens their very existence"