The end of the week when you finally get to grab your sexual interest and do your thing together.
More bluntly put; go out with your interest, down some drinks, listen to some music and fuck each other's brains out all night.
Chick 1: "where were you last night?"
Chick 2: "you kidding, it was Fuck Fest Friday! We were in every room!"
Chick 1: "ooh nice!"
A day that takes place on every third Friday of every month. This day is a day where friends go on and fuck/have sex
Person 1: it’s friends fuck Friday tmrw. Who are u fucking?
Person 2: idk maybe Rachel