The hair that covers your butt-cheeks.
May look disgusting sometimes, but still rocks when making fun of it.
Also good for showing your lack of respect for another person.
"Hey dude, let's go and set my buttfluff on fire."
"Shibby!"

or

"You're a dick man."
"Ah touch my buttfluff, ass eyes."
by Myname June 15, 2004
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