when your testicals have so much hair on them it looks like a muff on your balls.
Some balls are so hairy they look like giant ball muff
by LilJOnwhattt: July 29, 2005
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Someone who routinely hangs out in vaginas. Orginated from the film Stepbrothers:

Alice: "Oh, Dale. You are something. You are something."

Dale: "You're something too."

Alice: "I wanna roll you up into a little ball and shove you up my vagina. You could just live there. It's warm and it's cozy."

Dale: "In your vagina?"

Alice: "I wanna walk around with you in there and just know that whenever I feel a little tickle or scratch that it's just your hair up my vagina. Please, just do it for me."

Dale: "What's happening?"

Dear Dale - you are becoming a muff ball.
A lesbian friend of yours is walking down the street and you want to catch her attention, try: "oi muff ball."

You're on a date and it's getting hot and heavy. You say: "do you wanna be my muff ball?"
by Lupars September 28, 2009
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