Spirit Wolf by Suzanne Roslyn

She was only looking for one wild night to remember, but her wolf called to him, and Ryker Blackmar couldn’t walk away from his fated mate. In Lena’s line of work, relationships were dangerous and having Ryker’s baby could become deadly. She’s supposed to be keeping an eye on the Shadow Pack Alpha, but her eyes aren’t the only thing she can’t keep off him as Lena struggles to accept her wolf spirit. Ryker will have to make a deal with the Chief of Marlboro to save Lena and ensure the survival of their child.