Trash of the Count's Family, Cont

I also like the themes about how important information is, as well as cooperation and using that information.

Spoilers again... 

At one point the main character gets sent to the equivalent of his own past. That's where we really learn about the alternate Korea he's from. 

Anyways, he's sent back to one of the worst times in his life. Where he doesn't have his later abilities, where the monsters are going to go especially crazy, and where a lot of bad things happened. So he decides to change it... 

 And even though he's got a few advantages this time, the biggest one is actually his information. And experience. 

Which he uses to help train the people around him.

Its strangely hopeful, in that he comes from a post apocalyptic world where monsters destroyed pretty much everything... 

But he also experienced the post apocalyptic world where people learned how to use their various skills to cooperate and take down the monsters. 

He values abilities like recording and communicating, things that in the immediate aftermath seemed useless since they didn't kill monsters... Because he knew firsthand how collecting and sharing that information eventually did.