Any type of female genital piercing/vaginal piercing. While not common among females, freaky types may be more likely to have these. In any case it is a rarity, not likely to be predicted, thus it's relation to a diamond in the rough.
Homey: Yo, that chick you brought home last night was cute as fuck...

Dogg: Yea bro, you never woulda guessed it, she was freaky as hell.

Homey: Nahhh.

Dogg: Yeaa son, she had a diamond in the muff.

Homey: Damn. I didn't see that comin'.
by eboymonster March 3, 2011
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