The girl and the demon tells a story of a young demon boy called Theo who struggles with his decision of what he wants to do when he grows up. Upon arriving to the human world with his classmates, he gets lost from his group and ends up in a snowy forest. There he meets a little girl who mistakes Theo for her imaginary friend. Soon Theo has to make a decision of whether or not he is going to answer his calling.

[From official site]