柊様は自分を探している。

Hakuba Keijirou never had any interest in girls until he met a beautiful girl who was also very unusual. The girl was dressed in an archaic style and seemed to have nearly complete amnesia. The only thing she remembered was her name: "Hiiragi." Keijirou convinced his parents to take charge of her while they looked for her real family, and Hiiragi moved in. But who is Hiiragi, really? Is she a princess, who came through some kind of time-slip? Is she something supernatural? Hiiragi herself would like to know...