"I'm not familiar with that" is simply a term to use when you're caught red-handed.
Cops: We caught you driving 75 in a 25.

You: I'm not familair with that.

Girlfriend: It's over! I saw you kissing Beth, you jerk.

You: I'm not familiar with that.
by trees-don't-grow-on-money June 17, 2009
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