Ume makes a living as a hunter while nursing his frail elder sister. In urgent need of a vast sum of money to cure his sister’s steadily worsening illness, news of a labor recruitment drive falls into his lap. While clearing roads for the reclamation of Ezo territory, a survey team and their forest guides suddenly vanished inside a certain "Forbidden Forest"——. To uncover the truth behind the disappearance of the advance survey unit, Ume joins the second wave of forest guides—a crew assembled from local roughnecks and renegades—and steps foot into the forest. There, he comes face-to-face with the terrifying white monster that dwells within this woods——.