If you see a girl that looks annoyed because some loser is trying to put the move on her then casually walk up to the two of them and don't say a word but start sniffing.
One of them usually says "What?" to which you reply... "Smells like bullshit to me!" At that point you've saved the girl and shown her you have a sense of humor also.
Caution: Don't try this if the guy looks like he could whip your ass!
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