4In New Imperial Japan, a superstitious population lives in constant fear of rips between the domains - doorways that allow the shadowkin entry. Only the emperor and his sentinels stand between the people and this legion.Tsumi is the youngest of his warriors, ever favored by the emperor. Even as a teenager, she knows her success as a sentinel is imperative for her family's standing. But not everyone shares his love of her. The teen's lineage separates her from the others in the court. Most treat her as the outsider.When townspeople disappear near a dense forest, the authorities are ill prepared to investigate. They are not qualified to help when those who return are... changed.With legion's arrival imminent, Tsumi stumbles on secrets hidden in the Sea of Trees. Victory requires a team. This knowledge will see Tsumi either become the next victim or the person able to defeat the approaching annihilation.