Solis, Kihnes, Zemē and Iriya. The realms of magic, nightmares, technology, and souls. Only one being can move freely through the four realms, a shadow-bound fae rejected by his people as his powers arose. Death walks alone through the four realms, collecting the souls of the damned, judging their next paths of rest, rebirth or repentance. Princess Keziah of Quaver is the second born princess in one of three great siren courts of Solis. She is bound beneath a web of ancient magic, forgotten in the shadow of her sister, their heir, and feels invisible as she struggles with her place in the world. When Keziah meets Death, two invisible souls finally feel seen, and it sparks an obsession that transcends realms, spilling a river of blood.