The world at large doesn't know it, but Magical Girls are real.
We make contracts with Kyubey, usually somewhere between the ages of eight and eighteen. When we become Magical Girls, we make a wish that he grants. In return, we fight Witches. That's just the way of things, and it's a very dangerous line of work. Unfortunately, it's only a line of work as a figure of speech, so once you grow up it doesn't pay the bills. Or rather, you'd think it didn't.
There are a few Magical Girls, those who live long enough, who make a living off of it. The world at large doesn't know it, but there are some companies out there who are all too aware of Magical Girls and Witches. Corporations who, one way or another, came into the knowledge that there is definitely something else beyond this mortal frame we call humanity. These corporations? Well, some of them will hire Magical Girls.
What could one possibly hire a Magical Girl for, you might ask. That's pretty simple. Think about any labor-intensive work, particularly ones that involve violence. Now consider how much better you could do said jobs if you possessed inhuman strength the kind normally afforded to Magical Girls. These places, usually shady corporate headquarters, places that deal in the weirder ends of science and medicine, they like to have at least one Magical Girl on call as a sort of special hidden security guard. A bonus boss fight, you could say, for any would-be meddlers. Some Magical Girls find their place as assassins for the top CEO's, taking out corporate rivals or subversive board members. Others are hired as personal bodyguards, and those positions don't come cheap by any means.
And that's where I come in. I'm a bodyguard for one of the top executives at this company. To anyone on the outside, I'm a co-vice-executive. Whatever that means. But I fight other Magical Girls who work for other companies, trying to kill my employer. I'm very good at it too. The only way to move up is if my employer's boss were to die. I want that pay raise, but I'm not allowed to kill the fossil myself.
My name is Junko Kaname, and I am a Magical Girl.