The Devious Husband (The Windsor's book 6) by Catharina Maura

He's the business rival she can't stand. She's the woman he's secretly loved for years.

Xavier Kingston’s life is turned upside down when his nemesis and business rival, Sierra Windsor, suddenly begins to show interest in a man that isn’t him.

Certain he’s at risk of losing his chance with her forever, Xavier offers the Windsors a deal they cannot refuse: a merger between his company and Windsor Real Estate.

On one condition: Sierra must marry him.