Akane lost her parents at a very young age and grew up believing she was a mistake and should not exist. Eventually she came to be in the employ of the J.S.D.F. On a mission against Godzilla in 1999, Akane accidentally kills upwards of eight members of the J.S.D.F. by accidentally bumping them into the path of Godzilla. Afterwords, she is retired from technician work to be a Librarian in the J.S.D.F. archives. Three years after this incident, she is taken out of her desk job to be a part of the Kiryu team. After Kiryu is badly damaged and left, for the most part, inoperable, she climbs inside of Kiryu to control him manually. Throughout the film, she develops a friendship with Sara Yuhara, with whom she shares many similarities.
In 2004, Akane was preparing to travel to the United States to receive further training. Akane was present at a banquet honoring the new team piloting Kiryu, but was very distant from everyone else, and wandered off to Kiryu's hangar. Yoshito Chujo, Kiryu's lead mechanic, followed Akane and spoke to her. Akane told Yoshito that she felt great pity for Kiryu, as she believed he didn't actually want to fight Godzilla. Akane asked Yoshito to take good care of Kiryu, and then left.