Kae is a Spirit Hunter in a post-apocalyptic future where humans had to make a pact with entities of a mirror realm to save the planet from complete extinction. In return for saving Earth, they were allowed to live alongside humans. Some spirits are benevolent and some are bad. She is employed by the world government to track down and detain wrong-doing spirits. Her discs are powered by two spirits which she made a pact with after detaining them. Kae is a fighter who is very good at what she does. She has a thing for energy bars and cute soft things!