I have read it until 180+ ch. But still confuse just who is the main enemy. Even the dark ...

I have read it until 180+ ch. But still confuse just who is the main enemy. Even the dark lord give hand to them, to destroy the true enemy. Mannn..I'm more confuse abt the connection between the other world and current world. Like is causality a person or what. I'm confuse rn someone please explain I really want to understand. Maybe my English not good. The more chapter the more It become more serious, I want the comedy back （￣へ￣）