Bakemono no Ko

The story is set in the human realm (Tokyo's Shibuya ward) and the bakemono realm ("Shibutenmachi"). In these two worlds which must not intersect, there lives a lonely boy and a lonely bakemono. One day, the boy gets lost in the bakemono world, becomes the disciple of the bakemono Kumatetsu, and is renamed Kyuuta.

(Source: Anime News Network)