It's goin' down like the Catalina wine mixer
from Lil Wayne – Wasted Lyrics on Rap Genius
Meaning
A double entendre:
The “Catalina Wine Mixer” was an integral part of the 3rd act of the Will Ferrel Movie Step Brothers, where the brothers have to fill in for the missing band at the last minute (it’s a helicopter expo in the film, hence “going down”, I guess)
A “Catalina Wine Mixer” is slang for the sexual act of inserting 3 or more red grapes into the pussy and using your penis to juice the grapes
Hence, because of the wine mixer’s location, it’s “going down”

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