Spirits.

In the East they are called yokai, in the West they are monsters.
The word was popularized long ago by researchers and believers seeking to put a term on life beyond the known.
Among spirits, some take the form of humans, and exist not only among us but interact with us fully.
One research institute categorized these special spirits as "jinyo".
A further revelation was made: if jinyo were among us, then there were also offspring of jinyo and humans.
Known as "crossbreeds", these humans were born with the supernatural abilities of spirits.

This is the story of young crossbreed girl Yozora Fumizuki, and the spring love with a boy.

[from DLsite English]