What is Grundle Butter?
1.
Grundle (Aka-Trundle) being the area between your balls and your asshole.
Butter being...butter
Grundle Butter is greasy Sweat that gathers in the Grundle region, Semi-transparent in color with a refreshing odor.
SFM-Trundle Butter
"Why is Steves asshole wet?"
"Thats just his Grundle Butter."
"Poor Bastard"
2.
An unfortunate gelatinous sweaty buildup on the grundle (which is the hair and area between your genitals and arse-hole).
I pulled off my jock and found a pat of grundle butter on it.
3.
n. sweat from the balls and ass crack that congeal in the taint area.
'man, it's so hot today... i have so much grundle butter'
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4.
The left over cum on your dick and the cum that seeps back out of your partners twat after intercourse eventually mixing together and settling in your crotch.
I could have had a fish fry with all that grundle butter.
See