VIDEO : Did Brody Jenner Throw Shade at Tyga?

Brody Jenner used a porntastic image to send a message to Tyga -- quit banging my 17-YEAR-OLD sister, Kylie Jenner -- or so it appeared. Brody posted the illustration this morning ... of a tiger in the jungle licking the lady parts of a young woman with dark hair, who looks a lot like Kylie. Most people assumed he was making some kind of commentary on Tyga and Kylie's relationship -- but Brody's GF, Kaitlynn Carter, tells TMZ it was an innocent coincidence. Kaitlynn says Brody's friend has a t-shirt company and they were just looking for Internet memes to use on gear.??