Baif is a person that is typically Aboriginal, gay and has a really shitty haircut.
Person 1: Look at that Baif over there
Person 2: Yeah I know, stupid gay aboriginal
Baifs Nan, in other words that relates to an Aboriginal persons nan who gets done on the coffee table on the daily.
Man 1: Holy shit did you see Baifs Nan?!?!
Man 2: Yeah man, she looked fucking nice
Man 1: I would bone her all night