Akie Takasugi is a junior high school student at Saigawara 4th Junior High School and the childhood best friend of Yuzuki Mikage. With an outgoing and broad-minded nature, she stands in contrast to the more reserved Yuzuki. Her father, Norihisa Takasugi, serves as commander of the Saigawara Metropolitan Police Department.

Akie hired a private tutor named Azusa Mayama to help with her studies. Over time, Akie grew emotionally close to Azusa, who then disclosed her true intentions. She brought Akie to her home to reveal her bedridden, paralyzed father, explaining that his condition resulted from a traffic accident—an incident that Akie’s own father had ordered not to be investigated. This revelation enraged Akie, prompting her to leave her family home.

Azusa then revealed her plan to bully Akie through rape and ultimately use the Hell Correspondence to send her to Hell, intending to torment Norihisa. She carried out this act after the Six-script Lantern ceremony.

Later episodes initially implied that Akie had returned from Hell to assist Yuzuki after Yuzuki became Hell Girl. The final episode of the third season, however, clarifies that this was an illusion crafted by the Spider, the God of Hell, meant to tempt Yuzuki into breaking the rules by attempting to send Azusa to Hell. Akie remained in Hell and did not truly return.

In the finale, Norihisa Takasugi, devastated by the loss of his daughter and having lost his position as Police Chief due to obsessive investigations, accesses the Hell Correspondence. He requests that Azusa Mayama be sent to Hell for damning Akie. After spying on Azusa and witnessing her care for her ill father, Norihisa reconsiders, returns the straw doll to Yuzuki, and chooses not to complete the contract.