Celebrities, sports stars, CEOs have never been more at risk of ‘sextortion’ attacks, lawyers say.  Sexual encounters lead to threats: pay up, or I’ll ruin your career and reputation.  ‘Clients are terrified,’ says one in a growing field of lawyers paid big money to turn the tables. Loading Something is loading. A young Manhattan CEO looked at his phone in horror. “I’m going to blow up you and your business,” the screen read. It was a woman he’d met on Seeking Arrangements, the so-called sugar-daddy site. She’d told him she was of legal age. Now she was claiming otherwise.  The CEO had already parted with some $40,000 in money and…