Use of Japanese language
I've tried wherever possible to translate Japanese terms to English - Judgement Bureau for JuuOuChou and Summons Division for Shokan-ka, for example - but I've kept some terms which strike me as untranslatable, and proper names such as Meifu, Gensoukai, etc, on the assumption that their meaning is obvious from the context.
Japanese names are always written family name first - Kurosaki Hisoka, Tatsumi Seiichirou, etc. I have kept suffixes such as -san and -kun because many Yami fans are aware of the speech patterns of their favourite characters, and hell, I just like writing them. ^_^ However, I've substituted "lord" for "-sama", "doctor" for "-sensei", etc.
Quick guide to Japanese terms -
shinigami - god of death
shikigami - summoned god
Meifu - the world of the dead
Gensoukai - the world of the shikigami
Jigoku - the demon world
Yami no Matsuei is very much rooted in the Buddhist concepts of the afterlife, which are rather different from those in the West. The important thing to remember is this: Meifu is not heaven or hell, it is a limbo between one life and the next, a holding space before reincarnation. There are six worlds in Buddhism - the world of the gods (Tenjo - not the same place as Gensoukai), the world of humans (Ningendo), and then four lower realms, the deepest of which is the demon world (Jigoku). When a soul comes to Meifu, it passes through the courts of ten judges (the JuuOu), who decide where the soul will go next. A human can be reincarnated deep in Jigoku, or up in Tenjo, or anywhere in between, depending on how they have behaved in life. Similarly, a god can be damned, and a demon redeemed, by their own acts and eventual death.
It takes time to pass all the judges (probably because of the endless paperwork!) and so souls will "live" in Meifu for as long as it takes to move them on. Some pass through relatively quickly, others linger in regret or anger. When Hisoka arrives in the Summons Division at the start of Fade to Black, he's already been in Meifu for several months. On his thirty-fifth day, he reached the court of Lord Enma, the Fifth Judge. And after that, well... you'll have to read and find out. ;)