A shadow leaps to protect a small life — the shadow of a pet once kept by humans. Under the guidance of the mysterious Mr. Z, a group of protagonists work in the dark in the forms of therians, gradually uncovering the truth about the world as it has been shaped by their own creed. Humans and animals should all live happily. What kind of justice will these heroes — who love both — choose when the truth makes the answer complicated? A visual novel about protection and the costs of loyalty.