Rating for the Milan; haven't read the other two.
Lydia's family runs a bookshop. She has a crush on a customer to whom she's never spoken. When the family is in desperate straits, William offers to pay Lydia enough for sex to rescue the family's livelihood. He thinks repeatedly to himself that he doesn't care if she doesn't want to have sex with him. He wants to have sex with her. He knows she'll hate it. He doesn't care. So he rapes her -- but, wait, it's not rape! It's not rape even though he had sex with her believing she did not freely consent! Because she's in love with him (despite the fact that the only time they've spoken he essentially used her desperation to rape her)! She feels so sad for all his loneliness and trauma!
A lot of romance features rape fantasy ("forced seduction"), or romanticizes rape, or eroticizes situations that would be actionable in real life. Whether or not I like these scenarios or can't stand them depends on many different factors, including the balance between fantasy and emotional realism and on whether the characters and the narrative recognize these acts as problematic. In this case, the balance between the emotional realism around the more depressing aspects of William's and Lavinia's lives makes the fantasy treatment of their "relationship" (in which they never even talk to each other before the day William asks Lavinia to prostitute herself for him) completely untenable to me. The entire story reads like a rapist's wish fulfillment fantasy. It is incredibly repulsive.
I'm glad I read "Unlocked" and the Carhart novels before this, because if this had been the first thing I'd ever read by Milan, I never would have read her again.