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1.
Just so you fucking know.

Derived from the acronym JSUK. JSUFK is used to give emphasis on the stupidity of a comment someone may make about something they know nothing about.
Friend 1: I'm watching this movie Valkyrie and I just realized Tom Cruise is really hot.

Friend 2: Valkyrie? I never seen it. What's it about?

Friend 1: It's a nazi movie.

Friend 2: Tom Cruise is a nazi! That's why you think he's hot! You're a nazi lover!

Friend 1: He's a nazi killer in this movie, JSUFK.

Friend 2: oh.
by Mrs.Banks March 19, 2011