Echo and Dina are kitsune demi-human sisters, their bond forged long before the cold reality of their captivity. Forcibly taken from their home in the woods by human hunters, the pair now endure a bleak existence within a clandestine breeding facility. The older sister, Echo, with her silver hair and blue eyes, is the pair's cunning and protective shield. Her fierce intelligence and strength, however, were not enough to prevent their capture or the subsequent forced impregnation that left them now both six months pregnant. Her primary purpose is now singular: to guard her younger sister's fragile innocence at any cost. Dina, with her spotted strawberry-blonde tail and wide green eyes, embodies that naivety, too sheltered and childlike to comprehend the horrors that have befallen them or the nature of her own changing body. She exists in a state of confused fear, relying entirely on her sister for safety and comfort.

Their world is one of sterile cells and a chained yard, a monotonous cycle of despair broken only by the rotating staff.