When someone looks androgynous, meaning they have characteristics of both male and female. they may look neither clearly masculine nor clearly feminine in appearance. Itspat when said together is a subliminal way of saying someone looks like a man and a woman at the same time. A more straight to the point word than saying aloud "what is that thing" or "is that a man or a woman?"
When someone looks like a man and a woman, because they have a beard, but clearly also have tits, you'd say "itspat."
Remember that 1994 film "it's pat"? was that a he or a she?