Cinderella is an agent for the Sheriff.
In the universe which contains the activities depicted in the series of various adventures known as the Fables, this fairy tale princess has been earning her keep and keeping herself entertained for the past two hundred plus years as the best secret agent the Fables never knew about.
The concept behind the Fables is that the various kings and queens, princes and princesses, heroes and villains, and so on that inhabited the fables and fairytales we all heard growing up, well, they actually all existed in another world, or worlds. They were driven out of their usually happy lives by a horrible conqueror called The Adversary and forced a few hundred years ago to flee their lands and transition (somehow) to this world.
They have dwelt supposedly in a "magically hidden neighborhood within Manhattan" from where they live their lives sometimes associating with humans and sometimes sticking with their own.
In this Fables universe, the well-known hero and/or love interest to several beautiful ladies/princesses, Prince Charming, is really a bit of a cad. He is without a doubt incredibly charming and able to woo virtually any woman he sets his mind on but, alas, he admits quite candidly that his love for each of these fair maidens, and he does indeed love them, is fleeting and so his wandering eye invariably spots another challenge and all he goes.
Cinderella is the third Mrs. Charming, as far as we know, having followed Snow White and Sleeping Beauty (aka Briar Rose).
Her origins are pretty much what everyone knows them to be. She was the daughter of two wealthy parents who loved her very much. Her mother dies as some point in her early years and her father remarries to a woman with two daughters of her own. After Daddy passes away, Cinderella was left to the horrid machinations of the step-mother and step-sisters and she was forced into a life of servitude.
Then came the time of the ball and with the aid of her magical ... well you know the rest. At least up to the point sometime after the wedding and the hope of happily ever after.
What we learn in the Fables chronicles is that just as Prince Charming had already left two beautiful former princesses, he fell prey to his instincts and found pleasure in another woman's arms.
Cinderella did not take this at all well and a divorce was in the works when the armies of The Adversary arrived creating mayhem throughout the land and forcing the powers-that-be to flee in what is called The Exodus. Upon their reaching this plain of existence, Cinderella promptly finished divorcing her cheating hubby and started a new life.
Two things would occur her time from then one.
One is the shoe store she opens to earn a living and at least appear normal. It is called, not surprisingly, the Glass Slipper.
The second is that she would take another, covert job as a secret agent for Fabletown, working initially for a person named Bigby Wolf and then later for someone called Beast.
According to the Fables Wiki (see Links below), "Cinderella has described herself as an excellent spy, a competent assassin, and a lousy diplomat. She has a mean streak and has a habit of making men angry. To better maintain the secrecy of what she does, Cinderella puts on the facade of being an air-headed valley girl."
We are shown in the various appearances she makes in the Fabletown adventures that Cinderella is a beautiful young woman with quite fair skin, blue eyes, and blonde hair, worn medium length. She has an excellently toned and athletic body which she keeps in great shape with constant exercise.
- Discussing the troubles of a thousand-year marriage to the Beast, Belle (Beauty) observes, "No one can be perfectly blissfully happy and in love for so long."
- Introducing herself on her first fully recorded adventure, "My name is Cinderella. Cindy to my friends. Don't tell anyone but I'm a spy. One of the best, even if I am being humble. And there are times I love my job."