A research framework (Paulhus & Williams, 2002) describing three overlapping non-clinical traits: narcissism, Machiavellianism, and psychopathy. Not a diagnosis — a personality-research lens for understanding manipulative interpersonal styles.
A boss who self-promotes constantly (narcissism), strategically uses people to get ahead (Machiavellianism), and doesn't seem fazed by the harm they cause (psychopathy) is what dark-triad research describes. None of those traits alone is a disorder; the combination is what's predictive.