Awakening in a mysterious forest with no recollection of his past, a man encounters Kuon, a young girl with animal features, who guides him to safety in her village. Dubbed 'Haku' by Kuon, he realizes his uniqueness in a land where everyone possesses animal traits except him. Together, they embark on a journey to Yamato's capital, encountering allies and foes while unwittingly entangling themselves in the political intrigues of the realm. As Haku navigates this foreign environment, he strives to unravel the enigma of the red slimes and prevent escalating conflicts between neighboring nations in Utawarerumono: Itsuwari no Kamen.