Short for "should have been a cum stain". Term for a person who is absolutely useless.
The guy or gal who comes to a party that doesn't help in any way. Sits alone in a corner, can't get a date, never has their own party supplies. Most of the time no one notices them.

He'd been a better Shobacus instead of being born.
by Buzzweiser July 13, 2011
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