Demon Flowers: Kuruizaki No Hana: Volume 1

The Oni have been searching for the 'out-of-season flowers' - children born from the union of Gods and humans. In the midst of this, an Oni called Ushitoru saves the life of one such child, Masata, and steals him from his family. Now 11 years have passed, and Ushitoru, Masata, and a young human girl have become an unusual family.