Aki started out as an orphan with her sister Kyoko on the home Arume planet. Like most Orphaned Children, when she came of age she joined the Arume military with her sister. She showed a lot of promise, and talent in the military, same with her sister Kyoko but Aki was always slightly superior in whatever they did. Over the course of ten years she rose up the ranks and became a commander and as she got promoted the plan to invade earth took place. She felt pity for the humans and somehow, sometime decided to join the humans to fight against the Arume. We do not know why she felt this way, or what the reason was for her to go against them.
According to Willhelm, her second in command who later betrays her, she helped him escape prison along with some other men including another one of her faithful soldiers, Dimitri. She did all this while still acting as a commander for the Arume.
She first appears to the players in the Louisiana base (season 1 episode 5 of Noobverse), and her appearance was not received very well. The soldiers had no idea that she was an Arume, since she used a voice changer when talking to them through the radio. But eventually everyone accepted it, and she was welcome aboard.
Aki has long white hair, and purple eyes. She wears an old military jacket, a white shirt under that with a tie, a skirt and thigh highs. She occasionally wears a beret when she wants to look serious, usually when she's giving a speech or a mission briefing. She's 167 cm tall, and has about an average boob size.
Aki could be said to be a kuudere, especially when she is first introduced, however as she got closer with Jeremy her she picked up his sick sense of humour, but she only lets out that humour when with him. She will not allow herself to look like that among her men, and manages to have a very strong and stoic personality in front of others.