Take Me I’m Yours (Forbidden Billionaires Book 1) by Lili Valente

I'm not supposed to want my ex-boyfriend's dad. But after one scorching night last summer with a sexy, older man who instinctively knew how much I wanted to be called his “good girl," I can't stop thinking about him. Of course, back then, I had no idea who Gideon was. Still, we both agreed that one night was our only night. Our lives were too complicated for anything more, no matter how much I craved it. Then our paths collide again at my ex’s fundraiser. That’s where I learn the truth about who Gideon really is. I also learn that he’s forbidden with a capital F. I know I should stay away from him, but this “good girl” is suddenly ready to go bad. Very, very bad. We can’t have a future, so we agree to take it one wild night at a time. Until an unexpected betrayal threatens to bring all our dark secrets into the light…