I read a story and want to read it again, but can't remember it. A girl decides that she wants to have sex with her Father, who is a preacher. She knows that he has sex with women other than her mother, so she arranges things so that she meets him in a dark room of the church and fucks him for the first time. Afterwards she discovers that he knew all along that it was her he was having sex with, and under the guise of "preaching to sinners" (I think) he begins whoring her out and letting her have sex with other men. They pretend to be "saving sinners" to keep the details of what they do together from her Mother, until she finds out in the last couple chapters that her Mom is an even bigger slut than she is and that her Dad married her for that reason.
I'm sure I missed some details, or mixed some up, but hopefully there is enough there for me to get some help finding this story.