Sweet Surrender by Missy Walker

Sienna
He was determined to make my life miserable. I was sure of it. It started when we were kids, and now ignoring him was no longer an option since he hired me to clean up his image.
But I was a professional. I didn’t get to where I am today by letting anyone crack my veneer.
I could withstand my nemesis, Noah Goldsmith.
I had the man at the club to blow off steam. So Noah could go f* himself.
That was until he walked into my office one day and dropped a truth bomb that hit me square in the face.

Noah
I never really gave a damn.
Maybe that’s what got me into this mess in the first place, or perhaps someone was out to get me. Either way, I was desperate to save my company and had no choice but to enlist the help of Manhattan’s finest Public Relations expert—Sienna Black.
She’s my best friend’s sister and a major pain in the ass.
She’s always hated me, and now I have to find the strength to put up with her orders for the sake of my business.
But she’s pushing me to breaking point, and I need an escape. If I don’t get my fix from the pink-haired girl at the club, I might snap and lose everything I’ve fought so hard to build.

A steamy stand-alone with a HEA, in Book 2 of the Elite Heirs of Manhattan.
Although a stand-alone, the series is best read in order.