Blood the Last Vampire

This novel is set in Japan in the late 1960s, where the youth are organizing a violent uprising against the government. Part of this revolt is the politically active student, Rei, whose fate is one day, coincidentally, bound to a mysterious girl, Saya. An exciting criminal case, and a voyage into the discovery of vampirism, takes its course.

Saya, the main character, lost her memory and has been living with her adopted family. Her everyday life seems quite normal, except that she eats a lot more than she actually needs. Then one day she meets a guy named Hagi in a park. She is told that he has been searching for her, for a long time. Since then, her normal life has changed completely. (This manga series is proceeding quite a bit differently from the anime) A high school girl named Saya can not remember anything from her past. A handsome young man, Hagi, appears and something seems familiar about him. This girl is more than human with an ancient and mysterious past. She will hunt down and kill the monsters called Chiropterans.

Ukishima Shrine is located in an old, picturesque lakeside town. Shrine maiden Kisaragi Saya lives there along with her father, Tadayoshi. By day, she lives the life of a normal high school student at Sanbara Academy. By night, she hunts the Old Ones. Possessing supernatural physical prowess, the Old Ones prey on humans, and only Saya has the ability to defeat them. (Source: AniDB)