For a long time, Akane had been alone, her closest friend at that time Masumi Nishino being in a different school from her as she was one year younger than her. Coupled with her being timid and shy, she had been unable to make close friends with anyone. Eventually, Akane was made a Kämpfer sometime before the events of the series. During this time, she never encountered any other Kämpfer, and her only companion on this matter was her messenger Black Seppuku Rabbit. Initially attacking Senou Natsuru, confusing him for an enemy Kämpfer, she eventually joined him as an ally along with Sangou Shizuku and Mikoto Kondou.
During her time with Natsuru, she eventually began to harbor feelings for him as he was the first male friend she ever had. These feelings would grow to such an extent that she would get jealous and irritated whenever any other girl tried to spend time with him. At the end of the Light Novel, Akane was eventually chosen by Natsuru, but she was not chosen by him at the end of the Manga.
Akane is shorter and generally smaller than the other girls in her group. She keeps her brown hair in a shortcut, keeping her hair neat with her signature yellow headband. She is usually seen wearing her school uniform, with glasses and occasionally her library ID card. Outside of class, she wears casual clothes, such as a pink shirt and skirt. She has shown interest in gothic clothes while shopping with Nishino Masumi and Natsuru, though usually wears something more conservative.
As a Kämpfer, Akane's hair grows out to be more unruly and is colored red which reflects her aggressive nature. She apparently also gains perfect vision, as she does not require glasses while shooting, and her eyes turn from an emerald green to a bright red. She also loses her headband and wears a black choker. If Akane is wearing her school uniform, her sleeves are cut shorter to reveal her bracelet and black undershirt.
Akane is normally a very shy, quiet girl. She tends to mistake others people's speech as sexual comments, as shown when she goes to Natsuru's house thinking that he wants to have sex with her. She stutters often and is very respectful to people she meets. After becoming friends with Natsuru, she becomes more assertive, shown when she forces him to go on a date with her. She is also very protective of Natsuru, as he was her first male friend, causing her to fall in love with him. She becomes very jealous and irritated when he talks about Kaede Sakura and repeatedly tries to get the other girls away from him. She has a very low self-esteem, shown when willing to kiss Shizuku Sangō to pretend that it is Natsuru. However, her Kämpfer form is a polar opposite of her normal self. Akane becomes very violent, aggressive and bad-mouthed, constantly insulting everyone she meets. She often threatens Natsuru with her gun, forcing him to do things that she wants. Despite this, she seems to appreciate her partnership and is always there to protect him. Unlike her normal self, she is not afraid to talk about her romance with Natsuru, though he does not see this. She also dislikes being addressed with any honorifics, shown when she threatened Natsuru after he addressed her as "-chan".