Contraction of the statement "Its Just A Fish". This statement was used in the movie "white squall" when one of the characters had speared a dolphin; and when questioned as to why he engaged in this act, mentioned "Its Just A Fish!!!!" to partially assuage his guilt by making the dolphin less than a mammal- a cold blooding feelingless fish.
Dude, that girl left you man. Oh well She's an IJAF, you don't need her anyhow.