An average looking girl who tends to hang out with a more attractive girl who generally gets most of the attention and free drinks. Said 'sidekick girl' is usually left off to the side.
When Madge and Janey got to the club it was easy to tell which girl was the Sidekick Girl. Madge was immediately asked to dance by several men while Janey stood on the sidelines holding Madge's purse hoping some kind gentleman would at least say hello.
by Tabloid82 November 27, 2010