I've been waiting to read a premise like this, mainly a sci-fi setting intersecting with a fantasy world, and they even provide an explanation as to how said fantasy world might exist parallel to our own and with scientific explanations to boot.
Considering how much they're setting up the conflict with the bugs even as far as Chapter 5, I imagine it'll be a plot point down the line that said planet is going to be visited by said threat sooner or later. Though I'm hoping the manga does reach that point.