Oni Wars Background Story
 Imagine this… aside from the world which you are existing now…there are other worlds that are existing...they’re not really parallel dimensions… more like other worlds…what if this worlds are set like rooms and the only thing that separates this two rooms are a single wall...and if this wall breaks… people from the other room can go in…people from other worlds can go to another world… Nai is a world who has been at war with itself for centuries… ever since one of its two suns were destroyed…this world has been separated into two factions… Nai and Black Nai. One day… the wall separating their world from the demon world weakened...both sides now tries to get as many demons as they can to side with them…hence the Naian-Oni wars begins…6 years had passed since the 15th head of the Seiji Ninjas, Aoko Seiji(Keiichi's mother), has gone missing, and Keniichi, her eldest son had taken over,becoming the 16th head of the house of Seiji. Seiji Ninjas now is not limited only to the Seiji family, he had merged other family to form the Naian Seiji Ninjas to help fight in the war. They had maintain the educational system of the 15th head training students to join the military forces of Nai.  Nai
Nai had two suns before…however a tragedy happened and one of its two suns exploded. When it exploded... it caused an anomaly in their world…this anomaly opens up gateways…gateways to other worlds…it took a lot of the people of Nai to different worlds…trapping them there…The Queen had to do something… she closed this gateways…but at the cost of her life…  Nai faced another difficulty…its population had been greatly depleted because of the gateways...and now their leader is dead…  A prophecy had been made that the queen will be reincarnated and because of this the council decided that they should wait for the return of the queen…However… some don’t agree… hence the division of the Nai…  Several centuries have passed… Nai managed to control the gateways ( a descendant of Nai who was thrown to another world managed to return to nai and told them how they could travel in different worlds using the gateways… he is known as the Great Scholar)…they can now travel to different worlds...their goal...until they find the queen’s reincarnation…is to gather the Naian people who were thrown to other worlds…during their search they found the queen’s reincarnation however...much to their surprised…the queen had been reincarnated into 4 different persons… Nai now has four Rulers governing them…four young rulers… they now faced the task of reuniting Nai and bringing back all the lost members of their world. 
Naian Physiology:
 Naians have wings that they can hide when they willed it.
 In some worlds… they are immortal…they cannot die as long as they are staying in that place not unless he gets killed by a fellow Naian in that place… In some cases…they may not be immortal but they grow old slowly…some worlds is dangerous for them…it depends on the world…the reason why this happened is yet unknown… Demon’s are not actually lethal…but they can kill Naians… Because a lot of people had been to different worlds…a lot of changes happened to the average physiology of a Naian..but one thing is still common and that is their wings…
 Naian World: Also because of a lot of different worlds the Naian people had been to… there are a lot of changes in the way of life of the Naian people…because of this…the Government divided the cities into districts (ie. The Japanese district, The Midieval district etc etc…) to cope up with the naians way of life…  Naian Military:
 One of the four rulers (Ao Takahashi) had taken the task of taking care of the military forces… since she among the four grew up in a somewhat militaristic environment…she is the 15th head of the Seiji ninjas (who happends to be descendants of Nai) at a very young age. Naian Military training goes hand to hand with basic education… at a young age.. naian children undergoes basic training with the purpose of helping them defend themselves… when they reach higher levels of education (junior high level) they are given a choice whether or not they will continue military training or take on another career. Their career path is their basis for the type of education they will receive…their performance will be the basis for their rankings and positions…   Naian Government
The head of Nai are the four Empresses
1st Empress Mike Carrens
2nd Empress Aoko Seiji/ Ao Takahashi
3rd empress Linh Mei-ling
4th Empress Marhianne Carrens
Cities/districts heads
Michiko Seiji
Hirotomi Fuji
Harvey Smith
Andrew James
Jaimee Hall
Lorrainne Kitty
(.. I forgot all the names…will search for them…) 
The Council
Head: Angelicka
Gaurdian of the first: Angelique
Guardian of the second: Angeli
Gaurdian of the third: Angela
Gaurdian of the forth: An-gel
Black Nai
Head: King Zethar
Crown Prince whatshisname..forgot..sheesh~~
Merium Crystals- shards from the broken “sun” of former Nai….it is used as a type of shield and as a way to open gateways to other worlds."Pockets" - coin shaped, they are use to store thiings, responding to the command 'pocket'