One who sneaks into the background of a person or group of people posing for a picture, usually making a face or picking their nose, totally unbeknownst to the photographer.

Sometimes, the savvy photo-imposer will even squeeze in with a group of friends posing for a *guest phtographer.
Guy showing off pictures at work- "Here we are in New York, see the Statue of Liberty behind us?"
Co-worker- "Yeah, but whos that guy next to you scratching his nuts?"

Bill: Here we are at Joe's party, what a blast!
Dave: Who the hell is the guy next to you putting his tounge in your ear???
Bill: Damn photo-imposer, Janet said he grabbed her ass during the picture.
by topsidejoe September 18, 2007
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