When some one is cheated that person got horns. So if the person in question got cheated a couple of times or just to emphasize, you say that he got a bag of horns.
Hey you "bag of horns"!
Shut up you "bag of horns"

You see a guy's girlfriend on a disco cheating on him with a couple of guys and then the other day you see him and say.
-Hey what's up with that bag?
+Which bag?
-OF HORNS!
by milo007 August 6, 2011
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