The word schme-mmen can be used in a variety of ways as it has no specific definition. It can be used in a positive or negative way to describe a person or body part.
"I love my schmemmen, we've been dating for a few months now."
"That schmemmen is blocking traffic!"
"Stop being a schmemmen and jump in the water already its not that cold." (schmemmen as in "chicken")
"Schmemmen, stop wasting my time."
HOLY MOLY, Thats one hell of a schmemmen she's got there!"