Hakoniwa No Fräulein. Satou Akira, while looking for a ghost that helped him as a child, has run into a decent amount of spirits that he does not even see. One day he goes for assistance to a supernatural detective agency and he meets the cute Yui and her devoted butler Kujou. Using her power, Yui ends up helping him with a number of the dangerous supernatural disorders in which he finds himself. Akira begins to feel attached to the detective agency, and wants to know more about the supernatural!