A man descends from the mountain, confused and with no memory of his past. He finds refuge in a struggling village buried in snow, they take him in and teach him of their ways. Haunting the village, however, is the Night. A species that hunts humans for unknown reasons, not just plaguing this village, but all the continent of Sirius. Follow Yukio along during his adventure to rid Sirius of the Night and watch as he discovers his true nature.