Well, that story wasn't anywhere close to done. That obviously got canned. It started off a bit creepy, but the story was actually starting to get good, as the main plot was starting to reveal itself, so it's kind of a shame.
there should be some sort of crowdfunding to revive actually decent projects like this, i know there is a lot of offer everywhere in the manga world but there's also so much stuff that's barely readable, it sucks when something with actually good art and with a plot that was improving a lot gets canned like that and there isn't even a novel to continue the story
I know it looks axed as the stink is that, but it seems that the mangaka got some health issue.
If is real the fact the serie was completed like this instead of being put on hiatus until they recovered is not a good sign...
Hope in a swift recovery.
It's cause the author was coming off from a more successful series before and probably got habits from that. So they wrote the story to have way more plot device than advisable during the period when it could be cut...
Which is probably also why this series failed....
By starting out with less, it allows you to focus on the main characters more and let's us know the world, while also giving the story a better chance to have a better end....
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TL;DR Author wrote a plot for an entire series rather than a closed arc, so it became hard to give it a proper ending in a few chapters. And writing too much for the whole arc also diluted the chances to get closer to the characters....