SlothfulCobra posted:

There was a story I read where humanity is involved in a massive foreverwar across the galaxy with a race of bugs, and then one ship gets nearly destroyed and the last surviving crewmember has to escape down to a nearby planet that has a medieval level society. Eventually the ship's computer analyzes the situation and says that help won't be able to arrive in a thousand years, although it was possible the bugs would arrive in a couple hundred, so the survivor decides to build a new kingdom to prepare the world for the bug invasion and give it a fighting chance.

Which seems interesting as a premise, but then it's just a slightly different twist on the old isekai formula where the protagonist gets ahead with cheat abilities (in this case nanomachines and guns) and uses his future knowledge to make such amenities as a hair dryer, and improbably the supporting cast is mostly women who feel extremely obligated to him. I guess it's pretty rare for a manga to run with a sci-fi premise like that in the first place.