Housuke Atami is dating Shizuka, the hottest girl in school, but it's just a platonic relationship. He and his friend Shinohara channel their frustration into secretly videotaping the girls' locker room. One day, they meet a mysterious girl of striking beauty; around the same time, the school is rocked by rumors of the "ghost" of a former beauty queen student. Shizuka notices a radical change in Housuke's behavior and makes up her mind to follow him.
This time around, the demon is trapped inside sexy but wholesome schoolgirl Izumi, but is unable to get up to its usual tricks (rampant orifice invasion) thanks to the crucifix that she wears around her neck. Out to locate and destroy the monster are a nun and a priest, but their efforts are hampered by Izumi's evil protector Sakiko, who does her best to help the girl realise her true tentacle-thrashing potential (and, in a Carrie-style side story, also settle the score with a group of nasty school bullies who have been making Izumi's life hell).