King of Sloth (Kings of Sin, 4) by Ana Huang

He'd never wanted anyone enough to chase them…until he met her.Charming, easygoing, and rich beyond belief, Xavier Castillo has the world at his fingertips.He also has no interest in taking over his family's empire (much to his father's chagrin), but that hasn't stopped women from throwing themselves at him…unless the woman in question is his publicist.Nothing brings him more joy than riling her up, but when a tragedy forces them closer than ever, he must grapple with the uncertainty of his future―and the realization that the only person immune to his charms is the only one he truly wants.***Cool, intelligent, and ambitious, Sloane Kensington is a high-powered publicist who's used to dealing with difficult clients.However, none infuriate―or tempt―her more than a certain billionaire heir, with his stupid dimples and laid-back attitude.She may be forced to work with him, but she'll never fall for him…no matter how fast he makes her heart beat or how thoughtful he is beneath his party persona.He's her client, and that's all he'll ever be. Right?