A thief runs afoul of her city's bloodthirsty nobility when she accidentally binds her life to the charismatic half-monster bodyguard of a royal house in the first of a riveting romantic dystopian fantasy duology rife with fallen gods, monsters and the deadly songs that compel them.

"A dangerous pair. A boy in disguise as a monster and a monster in disguise as a girl."

Ever since her firebrand mother died in a failed rebellion, street-thief Blink has sought answers about her strange ability: a siren voice that can command monsters. It's an anomaly, a power unique to the god-bone instruments wielded by the city's ruling Maestros. Music is forbidden to the lower reaches of society-so when Blink's only friend is caught helping her steal from the musical archives, he's sentenced to death by the city's most infamously bloodthirsty Maestro, Nadareina.

Sef has been Nadareina's bodyguard-more her pet-ever since she spared him from the massacre of his noble family and anchored a monster beneath his skin. Now unbreakably bound to her, he resists the monster's slow, inevitable takeover. But when Nadareina demands he join her onstage in slaughtering prisoners, an agonizing parallel to his family's demise, Sef decides to send her performance up in flames.

When Sef's sabotage interrupts Blink's attempted rescue, Blink accidentally calls a song that transfers Sef's bond from Nadareina to herself. Now, with her friend still captive and nightmarish monsters hunting them, Blink and Sef are forced into a tenuous alliance. But Blink's plan to outplay Nadareina from the shadows is hindered by Sef's drive for vengeance-and the ruinous attraction growing between them. And as the dangers they face accelerate Sef's monstrous transformation, Blink must ally with the doomed rebellion her mother started-or join her in the ashes.