In Bunker Gamma, the only sky Oriana has ever known is made of steel, and the hum of machinery is the only song of survival. Life is a cage of recycled air and rigid purpose. Once a year, the bunker pays the "Steel Tithe"-a tribute of blood and youth to the Luminis, the god-like beings who saved humanity from the sun-scorched surface. It's an honor she has never believed in.When a terrified young boy is chosen for the Tithe, Oriana makes an impulsive choice that will seal her fate: she volunteers to take his place.But the surface city of Aethelburg is not the paradise she was promised. It's a gilded cage of breathtaking beauty and chilling perfection, where the advanced Luminis rule with serene grace. Beneath the utopian façade lies a terrifying secret, and Oriana soon discovers the "donations" are not just for survival-they are a harvest of something far more vital.Forced into an unlikely alliance with Jaxon, the disillusioned son of Aethelburg's ruthless leader, Oriana must use her engineering skills to uncover a conspiracy that threatens to consume what's left of humanity. Hunted by an enemy that is both perfect and parasitic, she must find the truth before she is emptied of everything she is.Can a lone mechanic from the dark ignite a revolution in a city of blinding light? Or will she become just another sacrifice to a perfect world built on lies?