Non-binary generally refers to people (or unicorns :) ) who do not identify with the gender binary of man and woman. They may express themselves as somewhere in between traditional male/female gender norms, or oscillate between them, or express as completely outside those norms and roles. The most commonly used pronouns are they/them (as often used when referring to a person we don’t know, for example in, “Oh dear, someone lost their umbrella. I wonder if they realised. How can we get it to them?” ).
When did the eyepatch change eyes?