雷光の退魔師ナナホ～淫神復活～

Nanaho "taimashi of lightning" gets swayed by the overwhelming horror! Millay is a beautiful police woman who investigates on serial missing cases.

Her investigation leads her to suspect a private school named Watayama which sits in a certain gloomy town.
Then a mysterious pretty girl, Nanaho, shows up before her as a hunter of the evil.

[From DLsite English]