The white dog is apparently small and weak, and that black dog wants a fight, she has no way to win here. She seems very nervous and ready to leave the fight before it ever starts.
***A very clever concept, Jen. The black dog is scaring this little white dog right out of the picture. The empty chair and that long line on the floor suggest a dog fight is about to take place. The only thing missing is the referee, a very small referee at that, who would sit in that little chair and decide who wins and who loses. (An idea worthy of Elliott Erwitt.) Your choice of black and white to tell the story of a contest between a black dog and a white dog is excellent. Normally, we wouldn't chop off the legs and butt and tail of that poor little white dog. But since you have cast the white dog as hopelessly outgunned, your crop, which I find jarring, can be interpreted as sucking him right out of the game before it even starts. You are a very clever photographer, Jen Zhou!