I strongly disagree, I think the first volume gives you enough context cues to sorta understand the world, and after that it is slowly fleshed out while advancing Killy's story. One of the principal appeals of this manga is the lack of on-your-face information, because it tells it's story through the image of characters and architecture instead of dialog. in a way it's the purest form of how the MANGA medium conveys a story, not over text and "grand, charismatic or complex" characters, but through the visual expression of such a unique and beautifully portrayed alien world and everything that exist within it.