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A person whose behavior leads you to doubt whether they are, in fact, a member of the human species.
A man randomly stops you on the street to ask you why there are no recycling bins in this city, telling you what a shame it is, and asking you who could possibly change this situation.

After you manage to break free from his insanity, you turn to your friend and say, "Man, what a fucking space alien!"
by Depreciator1 February 25, 2010
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