Sekai wa Owattemo Ikiru tte Tanoshii

Today, there'll be discoveries and encounters again. For the girls marching forward in a world in its afterlife, there are still various things to experience: The remains of an extinct civilization, other living things, as well as lessons taught by the ruins... there is still a lot to be seen in the world. That's why... living is still fun! (Source: Overlap, translated)