Acronym - for 'Fuck Off For Now'. Used to end a text conversation when you want it to finish but do not intend to be rude. FOFN is a tongue-in-cheek way of saying: "this conversation is over for now."
FOFN is the FINAL word. Once used, the conversation is OVER.
blah blah blah
blah blah blah (with Texan accent)
SILENCE. The conversation is over!