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The thing you hear before the FBI busts through your door and raids your entire house for loli.
*knock knock knock* FBI OPEN UP WE KNOW YOU'RE IN THERE
by Frank Grimey Grimes July 14, 2018
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Aug 11 Word of the Day
A phrase to describe someone who is cognitively degenerating. Synonym of "going off the deep end". Can have varying degrees of severity.

Reference to the song "Hey You" by Pink Floyd. The line "and the worms ate into his brain" makes no sense in an otherwise linear and literal narration throughout the lyrics.
"My boyfriend has a total case of brain worms. He told me the cat was bugged so the Feds could listen in on us having sex..."

or

"You totally stumbled over that entire sentence. Can't speak English all of a sudden? What, do you have brain worms?"
by _Jez_ October 03, 2009
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2
When you listen to loli breathing as you jiggle your sausage.
Loli: Onii-chan, what is this white liquid in my pee hole?
FBI: *thump* *thump* *thump* FBI OPEN UP! *doors and windows blow up and rifles get fired rapidly*
by someunfunnyguy69 July 23, 2018
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3
hentai uncensored loli?
oh I don't like where this is going.
kanna-san:Senpai....Deeeppeeerrr
fbi:fbi open up!
by virtualsadboy June 11, 2018
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4
When people online are being creepy, the people will comment/reply and say “FBI open up!” showing that if they used that behavior IRL they would probably get arrested.
‘I’m 40 and I like 14 year olds.’
‘FBI OPEN UP!!’
by Tom Holland’s Girlfriend January 28, 2019
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5
1) A quote telling you the FBI are here

2) A meme. THE END
Me: Downloads Movies
FBI: FBI OPEN UP
by NintendoNerd December 19, 2018
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