I personally believe that he is just piece of shit. Unhinged, greedy, selfish one. Some people are made this way, some people evolve into that state. I don't really think it's some sort of diagnosis.

It is a schoolyard bully mindset in adult language. Someone acts differently than your idealized version of yourself in the same situation -> insinuate that they are not just different, but they are so abnormal as to constitute a medical condition.