Are You Fuckin Serious. Used when an unblievable statement has been made in a chat room or on the street depending on who you are.
Mo: I hooked up with Renee 2day.
RUFS is short for "R U Fuckin Serious?!" Used for those occasions when "are you serious" is just not enough to question the seriousness of a situation.
For use as an exlamatory phrase, 'I was about to go dick deep in this bitch in the bathroom at da club until she opened her legs and it smelled like week old fish in a dumpster in the 100 degree sun and i was all like RUFS?!"