Another name for a beast known to live in a basement on Downer Street in Milwuakee, WI. This alleged creature is known to be quite the anti-social creature. He usually will not convene in places consisting of more than three or four other humans. Known to have a ravenous appetite consisting of McDonalds and Burger King. Also, the creature is not know to be smooth in interactions with other people. Most interpersonal reactions with this creature end up with one or both parties being embarrassed. Many speculate that Manbearpigs utterly horrifying appearance resulted from his mother getting pregnant via the water wheel (see definition) and then doing copious amounts of heroin while pregnant. If you see Manbearpig, avoid at all costs. He is known to be a compulsive liar.
I tried to talk Manbearpig into going to a party, but because a large number of people were there, he declined, stating that he would rather masturbate alone all night.