This image is a play on the idea that everyone has a dark side whether they like it or not, and along with your good side together they make up your personality. If everyone was nice all the time and just went along with what everyone else said and did then the world would be a very boring place.
Maybe your darker side, or your demons, are the competitive, ruthless or creative side. They could push you to think differently to everyone else, come up with new ideas, have your own opinion and challenge rules that most people conform to without questioning. Obviously if you let too much of these demons out then they are going to control you and cause you to think and behave irrationally.
So don’t be afraid to take risks and stray off the path a little, everyone has so much potential inside themselves, it’s just a case of finding the right way of letting it out.