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When you throw a McDonald's Shamrock Shake into a large crowd of people on St. Patty's day, resulting in a large crowd looking like it has been covered in a green semen. What might happen if a leprechaun skeets on 5th avenue in Manhattan.
1:"Watch this."
(throws shamrock shake into crowd)
2:"Oh my God. It looks like a leprechaun skeeted on them"
1:"That would be a St. Patty's Day Grenade."
by Mr. Charles McMeaty March 12, 2011
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