My Traitor by Nicolette Pierce

Remy’s view on relationships is clear to everyone who knows him. He doesn't do them. He'd tried once and paid the price in blood. And, not just his.

After an excruciating stint in an enemy prison — thanks to Ava, the traitor who put him there — Remy is finally ready to move on. But Ava has other plans. When she returns unexpectedly, so does the haunting past, threatening not only his life and those close to him, but his conscience as well.

Ava needs Remy's help, and she won’t take no for an answer. She has no qualms about fighting dirty to get what she needs to survive. She's done just that her whole life.  However, fighting dirty with Remy was what ignited their affair so long ago. Sparks fly as the pair set out to right the wrongs of their pasts and fight the rekindling a passion both thought dead.