The act of instantly tanning one's finger by swiftly inserting a finger into someone else's asshole, followed by an equally swift removal. To expedite the process, use the asshole of the "someone" right next to you, in any situation.
Robert: Hi Earl! Every time I go tanning, my fingers never get tan. What can I do about this?

Earl: Well Robert, my good friend Clive once told me about "Instant Finger Tanning."

Robert: Hmm, sounds interesting. How can I do that?

Earl: By sticking your fingers all the way up my ass Robert! That's how!

Robert: WOW! That sounds easy!

Earl: Easier than dingleberry pie Robert. Easier than dingleberry pie.
by 2slick December 10, 2010
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