(yes, I know you were originally implying that you'd commit violence, but in a lot of dysfunctional workplaces reporting a manager for something they did will have almost the same negative consequences to the reporter as if they'd just punched them)
My question is, why did a senior staff member have access to a new employee's girlfriend anyway? I'm guessing the new employee friended the senior staff member on Facebook. This just seems like so many cross boundaries.