Peanut butter inside” is a saying the rappers often use in songs, (Kendrick Lamar, Swae Lee) discribing that the inside of their car is brown or a brownish color. The car is Peanut butter inside.
Tanner: “hello friend, what color is the inside of your car?”
Trevontarious: “mannnnnn... that bihhhh peanut butter inside!”

(defined by Luke and Nick)
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Referring to a womans genitalia
“ yo how was that pussy last night”
My nigga she had the peanut butter insides
by Savagedro April 23, 2018
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