Is Your Dog Bulimic?

I have been seeing this mural for years in San Francisco, and this is the first time I had a clear shot: we were stopped at the light, and for once there was no car next to me, no junkers in the parking lot, just a perfect view of a very strange and wonderful piece of street art. Someday I really want to stop in and ask to hear the story--there's gotta be a story.