FAF - or 'Flex As Fuck', fullout - is used when something isn't just flex, but
more than flex. It can be used in a number of situations, when something is just to flex for words. It can come in especially handy when one is shown a picture of one another and you are
trying to describe a pose, facial
expression, etc.
HAND SYMBOL:
There is also an hand symbol / gesture to indicate that something is FAF. The symbol uses two call me sign, with crossed pinkies.
ORIGIN:
The saying / meme 'Flex As Fuck', or 'FAF', is it is commonly abbreviated, was found by two high school students from the arts school of Antwerp, Belgium, in 2016, when they were on an excursion in Leuven.