Chudaruma is in itself a Diabolus Ex Machina, but since the entire freaking setting already jumpstarts from this fact... it almost doesn't matter.
Most stories in a fictional setting will accompany that which is most interesting happening. Generally also that which is most powerful too! But since Chudaruma and the devils aren't actually interesting and are just looking for entertainment, and face no challenge... we aren't following them. But the entire world is basically theirs to control every aspect.
Dorohedoro writes with such genuine and sincere fun, convenience to happen what should be most fun, that it really works in favor of the story! Love this manga to death