There are open endings and there is this. I have to give it to the author for not even attempting to resolve any of the plot threads.
So much this. I don't think any manga has filled me with as much disappointment and hate as this manga has. I was absolutely loving the characters and the art, but the author just had no ideas for bringing the story to a satisfying conclusion. At least I can get some validation from reading the hate comments here and on MD. sigh
