Overall the manga is pretty fine. Still have some plot holes though.
The manga didn't explain jackshit why Emma couldn't have custody over Linoa after the dad's death.
I thought Miiko showed Maron a badass transformation magic when she was little hence why she was disappointed when Miiko turned out to be useless in high school.
I have zero idea about the world building in this series. If only adults could get out, why are there still adults there if the ghosts kill someone every day?