Hakuchuumu

Hakuchuumu is about a nine year old girl name Sachiko who gains the ability to enter into an alter-dimension like world which becomes a brief escape from all the unimaginable things she has to endure in her world, until she took her older sister Hinata there to hide her from danger and ends up loosing her in the process. Now she must search everywhere for her while trying to endure the countless obstacles that are keeping her from getting to where she needs to go while also trying to erase her deepest pain which may be unerasable.

(There is also a free little booklet you can get to explain a lot of the cultural and symbolic references in the book called "Explaining Hakuchuumu". Because free books cannot be sold here, it can be found on Google)