"Griefing" is a term from the 80s film, "Crash The Party" starring Chase Cross. It means a low-level ****-block (i.e., when a stud male screws up his own night for kicks just to screw with his less than beautiful friend---or enemy---when he's trying to bang some random fat chick.) My recollection is that when it happens to one guy, he says, "Good grief, Charlie Brown"---hence the term "griefing."