Akari Mamiya, a first-year student from Tokyo Butei High, idolizes the S-rank Butei Aria Holmes Kanzaki and wishes to follow in her footsteps. Despite only being an inept E-rank Butei, Akari's resolve to improve remains strong. After the idea of having an Amica contract (a senior-student mentorship program) with Aria is brought up, Akari submits a request form attempting to establish said contract. Her classmates and friends do not expect Aria to accept Akari's request, mainly because of the girl's strict selection process, but to everyone's surprise, Aria gives Akari a chance through a test, which Akari miraculously passes! However, Aria will not officially make Akari her Amica until Akari meets her standards. Training under Aria will be no easy feat, as she has to concurrently manage her relationships with her friends. Will Akari have what it takes to walk down the same path as her idol?

If you have a grudge against someone, you can access the Hell Correspondence website at the stroke of midnight, type in your grudge's name, and the Hell Girl, Ai Enma, will appear to grant your wish. However, the price for ridding yourself of such a burden is a steep one: in return for condemning the soul of your tormentor to Hell, your soul will also face eternal damnation. In her long vigil as the Hell Girl, Ai has met many willing to pay such a cost. In Jigoku Shoujo: Yoi no Togi, Ai and her enigmatic companions continue to carry out their work, ferrying soul after suffering soul into the depths of Hell. However, as of late, a mysterious girl has been following them. This strange child, unable to even remember her own identity, questions Ai about her duty as the Hell Girl. Who is this girl, and what connection does she have to Ai?