Based on a light novel series by Shibamura Jin, illustrated by Houden Eizou.

A long time ago, a sacred fox was deified as the guardian of the Mizuchi Family. Kugen the Fox was very wise and it could use various magics. However, because it was too mischievous, it was sealed into a small shrine in the hill behind the Mizuchi house by a priest.

During the present, Takagami Toru, a Mizuchi descendant, often dreams of a woman seems like a monster. The head of the Mizuchi household deduces that some sort of danger looms over Toru, and she releases the sealed Kugen in order to protect him. Contrary to what Toru imagines based on the legends, "Ku-chan", as Kugen is affectionately referred to, is not a dignified creature. Not only can it turn into a woman of great beauty, but it can also assume the form of a man.

Taken from animenfo