Eba Yuzuki has mysteriously decided to go to high school in the countryside. But despite Kirishima Haruto's objections, she is living in his home. Now he has to put up with a freeloading city girl and even worse, make sure Kanzaki Nanami, the girl he likes, doesn't get the wrong idea!

Hiyori, a small and timid girl, goes to school for the first time in a year since an accident left her hospitalized. Follow her as she struggles with her social skills, tries to make friends and maybe even a little bit more...?

The story tells the tale of Semi, a bright girl who goes in a magical time journey with the genius teacher Wai, in order to prevent the evil X from utilizing the powers of the magic cube for evil. Along the way, Semi and her math school friends run into history and math problems that they must solve with logic and wit.

Following the events of Jigoku Shoujo Futakomori, Ai Enma, the Hell Girl, has disappeared. Her former companions decide to lead normal lives, until their absent mistress returns to them with a new companion, and in a way that none of them anticipated. Yuzuki Mikage is a normal schoolgirl who soon comes to understand the Hell Girl on an intimate level. During a dream-like trance in the bathtub, Ai kisses Yuzuki and possesses her. So when Yuzuki's friend decides to type in the name of their teacher in the Hell Correspondence website, Ai makes use of Yuzuki's body to accomplish her own task of ferrying the teacher's soul to hell. Yuzuki is disturbed by her new circumstances and wonders why she was chosen to continue Ai's work. Unfortunately for her, the Hell Girl and her assistants resume operation of Hell Correspondence, and she is dragged along for the ride towards hell itself. [Written by MAL Rewrite]