HFS is an abrevation for How Fucking Sweet and has been to my knowledge first devised by some Slovene dude.
It is used mostly when people who don't want to type a lot are trying to say something is sweet
Mary: Hey, I just got a kitten
Joe: hfs
How Fucking Stupid! Doing something that is completely idiotic and without thought about the consequences.
A legislator wants to make it illegal for parents to spank their children. HFS!
HF-AGBA is an acronym standing for Hands, Face – Armpits, Genitals, Buttocks, Anus. Also known as the “Cheat’s Shower” it is similar in concept to the airplane bath or BBA (Balls Bum and Armpits).
I overslept, so it was HF-AGBA before dashing off to work.
GL & HF means good luck and have fun. It is nice to say this to people at the start of a game.
GL & HF in this minigames guys!
Hf Twitter reads one Vogue article and thinks they’re Anna Wintour