Kurau Amami

A mysterious young woman employed as an "Agent"—a freelance operative who takes any job that's potentially too dangerous or illegal to involve normal private eyes or the Global Police Organization (GPO). Although barely in her twenties, Kurau is already one of the best in the business, and the rumor is that there's no job she won't take, or anything she can't do. Very few know much more than that, however, because there's no one who really knows her, and her past is a complete mystery. In truth, the Kurau the world sees is actually the result of a freak accident, in which her younger self's body became fused with an energy-being called a Rynax. This is not a case of two beings sharing one body, though, as the two personalities have merged into a new composite creature that shares two different pasts. As a result, Kurau is the ultimate loner, not quite comfortable with human society and forced to shun close relationships with other humans, lest they discover her secret. At the same time, she longs to be reunited with her Rynax "Pair," whose essence sleeps inside her.

(Source: Wikipedia)