A man awakens in the snow with no memory of who he is or where he came from. He is soon after attacked by a large red centipede creature and is chased down a mountain. Just before it catches him, the man falls into a hole where a giant red slime creature resides. When the creature tries to follow him, it is swallowed whole by the red slime. A woman with cat ears and a cat tail throws a flash grenade into the cave and rescues the man from the red slime. She introduces herself as Kuon and takes the man to a nearby village where she is going to deliver medicine. As the man cannot give his name, Kuon names him Haku, mentioning that the name has a long history. Haku helps Kuon with jobs in the village, and is sent to work a broken grindmill. Rather than waste effort grinding grain manually, he fixes the broken water wheel so he can sleep. A man named Ukon discovers he has fixed the grindmill, but Haku asks him not to tell anyone so he won’t be requested to do more repair work. Later that night, a group of villagers that have left the village are attacked and killed by an unknown entity.