Responses
I do believe China has a gang problem. Or at the very least had one not too long ago. Though I doubt it's anything as bad as depicted in the manhwa. Probably exaggeration for the sake of the story. And in the case of those one, if there were martial artists actually as strong as these in real life, able to indeed use magic (call it what you want it's basically the same. :P) I bet real life would be the same as well.

Is modern China really ruled by gangsters/triads?