1.) The moist "ass-crack" template left on plastic chairs after a fat or generally sweaty person has been sat there for a good stint.

2.)When you've got a randomly itchy arse for no apparent reason and you need to go wipe it to sooth the urge, its normally "Cleft Oil" thats causing your problem, a mixture or fart and sweat and whatever else might be in your ass crack.
Eg of 1.) Hey look at that seat!! that fat guys just left and theres a "Cleft Oil" pattern of his ass on the chair! Dirty cunt!

Eg of 2.) Man i've got an itchy ricker!! im gonna have to go mop up the "Cleft Oil"...
by Paleblank January 16, 2006
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