Dubious consent and BDSM themes. Dark erotica genre. No buy link available yet (not yet released), but the book is on Goodreads:
Blurb: Kayla Sutton thinks it’s over. She now holds the leverage she believes will end her contract with her blackmailer, but Gage Channing isn’t going down without a fight. He’s turned the tables on her, cleverly making her submit under the guise of giving her a choice, and Kayla soon discovers that retribution isn’t so black and white when everyone around her has secrets.
She faced sexual servitude in Ultimatum. In Enslaved she was seduced into craving it. Now she must find the strength to either accept the part of her that craves him still, or walk away for good . . .
Author site/blog link: http://authorgemmajames.blogspot.com/