Firing her boyfriend, a wrongful termination lawsuit with that, gifting her a car. She wouldn’t exactly need to make up anything to get a judge to believe she had reasonable suspicions that her livelihood depended upon sleeping with that man. But not only that, any other woman who worked for said boss could use those same facts against the company if it was shown hires were aware of the affair.
It was unlikely, the courts could do much for him in this situation, but trying to sue would have been an OK thing to do if one could get it done on the cheap. It would bring the relationship to the attention of the owners who likely would terminate the boss because he’s sleeping with a subordinate does open them up to significant legal liability. Moreso if another suit has already been brought up against the company.