(black cat bastard) An individual who has always done more, seen more or felt more than you. e.g. After explaining about your recent holiday a Black Cat Bastard would inform you that they had been to the same place, stayed in a better hotel for a longer time period and had a much better or worse time than you. Also known as the concept of a Black Cat Bastard.
In the event of meeting an individual with the characteristics of a Black Cat Bastard mention in conversation that you have recently purchased a black cat and wait for the reply. For certain the reply will be something like this "I have two black cats both blacker than yours."