It's an age where aliens, monsters and other dangers threaten the Earth, and various heroes have risen to protect it. Supporting these heroes are the human defense forces, of which the sisters Kitajishi Miyuki...

Tae has been practically inseparable from her best friend Kiyo since college. And while Kiyo may be loose with women, Tae can always count on him for support - like whenever she crashes at his place to drown...