The story takes place in a world of virgin forests and rolling hills. Here, there live people who appear human, but have the ears and tails of animals. One day, Eruru, who lives in a poor, border village saves a masked young man who had sustained serious injuries. Fortunately, he survives, but with the loss of his memory. Tuskle, Eruru's grandmother, gives him the name Hakuoro. This encounter will soon change all of their lives.