I've realized in chapter 4 that the different world is dominated by the Demon King and seems to be that there are no humans and mostly composed of fantasy species like Elves, Orcs, Slimes, etc.. Although they may seem to be related to the ones we depict in our games and stories, there are some differences in terms of intelligence, culture, and character. There some norms that can be considered immoral to us, but normal for them like the Beastmen copulation, and so goes for them to us like the degrading of slimes from our world; vice versa. From what I've seen in the last 4th chapter, the ambassadors wear formal military wear that looks modern; I presume that their world is also modern. In a sense which they incorporate mostly magical technology in terms of energy resources, transportation, and telecommunications; you can imagine an advanced modern tech world. Thus, their world is equal and might have more advantages than ours.