As a boy in New York during the 1950's, a scumbag was a used condom lying in the street, or in any other public place, usually thrown from a moving car. It signified utter and disgusting worthlessness.
Stay away from him. He's a real scumbag.
A person who gives little care for anyone. Someone who enjoys giving pain to others meanwhile they can't take any to themselves. They enjoy backstabbing their "friends" and jewing them for money.
Hey, you know that kid Chris? He's a total scumbag.
#FuckChrisReid
That Chris Reid still owes me $600 from the work I did for him 6 months ago, what a scumbag.
kid; hey what are you carrying that bag around for?
man; oh this scumbag here isnt wet enough