This term comes from the episode of Spongebob Squarepants when Spongebob thinks it will be cool to have a jellyfish as a pet.
So he goes to sleep that night and ties the jellyfish to his bed, but it gets free and goes back to jellyfish fields where it gathers all its jellyfish friends and brings them back to Spongebob's pineapple. They start to play techno music as loud as possible, and it vibrates everything, even Spongebobs neighbors, Squidward, house.
Now everywhere I live everyone loves to havejellyfish parties 24/7. And these parties go all night long, you can feel your brain rattling from your bed.
Omg what the hell is going on over there?! I think they're having a fuckin jellyfish party! Goddamnit!
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