This manga was a pretentious, edgy mess where the ending doesn't make sense, the histories are confusing and the characters weren't fully fleshed out. Every chapter felt like a nihilistic emo and an unhinged optimist were having it out and somehow morphed into each other and somehow wrote this manga to continue to thrash it out. Although it doesn't say much, I have never seen such a chaotic blend of grim dark and optimism in my reading life.
I love it. It was weirdly cathartic, some of the plot twists were genuinely surprising, and I believe the story's message could have been more clear and coherent if written better. The characters were interesting, and the premise is simply so interesting: the world is going to end; how are you going to react to it.
I'm genuinely interested in how the author would write or rewrite this if he committed to it. This has lots of potential, and low that he has gained more experience, it would be interesting how he can rewrite this. It's a shame that he said he has no interest in returning to it.