By accessing the Hell Correspondence website at midnight, one can request the Hell Girl, Ai Enma, to grant their wish of vengeance against someone they hold a grudge against. However, the price for such a service is steep as the requester's soul will also face eternal damnation in return for condemning their tormentor's soul to Hell. Despite this, Ai has encountered numerous individuals willing to pay the cost in her role as the Hell Girl. In Jigoku Shoujo: Yoi no Togi, Ai and her mysterious companions continue to escort suffering souls to Hell. Yet, a peculiar girl who cannot recollect her identity has been trailing them. She challenges Ai on her duty as the Hell Girl. Who is this girl, and what is her connection to Ai?