This is a conbadge for squeeji over on the realmediaexchange on Livejournal.
It's their character Friday who is a saluki/Iberian hound cross who really digs 30-50s style clothing.
So I drew her as a femme fatale. I used a reference picture to get an idea for the pose and in the ref pic the model was holding a gun, so in a toony style I decided to make Friday hold a banner with the word bang! on it instead.