Sin Dealer by Don Bellmore
I don’t think this Bellmore was written by George H. Smith, who had the Bellmore pen name, as well as Jan Hudson (and wrote some interesting SF books under his own name).
This is the first Nightstand/Midnight/Cornith I was unable to finish. I got about 60 pages in and tossed it aside it was that bad.
The narrator is a talent agent and a former client, a washed up but rich actress, offers to pay him good money to take her on as a client and re-vitalize her dead career.
Bad dialogue, bad writing…bad book.