The Devil's Angel (Book 1 of The Angel Series)

I was an Angel living in the Underworld, somewhere that I never thought I would end up when I died and was sent to the High Heavens.
I was an Angel with different skills because of my time in the High Heavens that the higher ups that I served thought would be able to use to "help" someone down there, someone that wouldn't admit that he needed help or needed a stable person that wouldn't fear him the way others feared him and had lived with him for many, many years.
I was an Angel that lived as one of them, living as one of his mistresses and hiding the fact that I was an Angel, even though the main king himself, who was the one that needed help, and one of his trusted friends and comrades knew what I was.
I was an Angel living in constant "fear" of being found out and not knowing what was going to happen to me after the fact, even though I knew, well hoped, that I would have the king's protection if I was ever found out by the majority of the people that lived there.
I was an Angel that had a way out from the Underworld and back to the place where I used to belong if I ever needed it, but the only catch was the fact that I had to stay pure and "innocent" like I had lived and died.
But that was difficult with a spark appearing between me and the man that I was there to help, to make sure that he stayed sane and able to live and keep his position as king of the Underworld.
For I was to be known as the Devil's Angel...