Thank you to all for your comments. Yes, the silhouette was intentional but I didn't get a good result I guess.
Maya didn't want to cooperate to much, it seems she smelled something in that side of the road...
I like the idea of this photo but the composition lacks a little bit, I'd like to see the dog slightly more to the right so that more of the view is revealed and more detail on the dog's head. It's a wonderfully conceived idea, because we all understand the excitement a dog has looking out a car window.