This is one of the worst pieces of unfunny crap I've ever seen.
The entire point of the movie seems to be to see how many times the word "fuck" can be worked into a sentence, and how many times this or that action can be referred to as "fucking (someone) up the ass" or "being fucked up the ass."
Now, I have no problem with "fuck" and its many variations; I use it quite often myself. But merely throwing 15 variations of "fuck" into a sentence does NOT make it funny. If a line is not funny without "fuck," it isn't any funner with it, either.
I'm also a bit of a "diehard"-- once I start to watch a movie, I watch it all the way through, even if it's quickly apparent that the movie is a piece of crap. Not with this one, though. After about 45 minutes, I became so fed up with the sheer stupidity and brainlessness of it that I said, "Why am I wasting my time on this crap?" and turned it off.
My only consolation is that I was watching a rented movie, and hadn't actually paid to see this pathetic piece of crap in a theater.