The story takes place in the largest Black Spot, adjacent to Tokyo. This area is under the unquestionable control of the Simeon Pharmaceutical Company, the only ones authorized by the Japanese Government to legally establish a presence in the Black Spot. They are located in the epicenter of the Black Spot, from where they conduct their business mostly unhindered
During the Third World War (prior to the year 2130AD), all of the nations of the world allied against Japan in order to obtain their advanced technology. This resulted in the bombing of Japan by the allied countries using various type of bombs. The resulting nuclear fallout created contaminated areas which fell into ruin and were immediately closed off and renamed Black Spots.
This quarantine is enforced by a huge, heavily guarded walls encircling all Black Spots. They were named as such because they appear as black holes on the surface of the Earth at night, devoid of any modern technology such as electricity. Eventually, among the inhabitants who were left behind in these Black Spots, came individuals possessing supernatural powers such as Wind, Fire, and Gravity. Fearful and ignorant of the forces of nature that they could control, people began to call them "Needless."
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The true history of the black spot involves Japan developing dimensional weapons at what is known as the black spot, and was previously known as "National Space Development Center".The NSDC was a front for the country to actually develop dimensional weapons.
The dimensional weapons related to nuclear energy could in theory turn the tide of battle. Initially designed to move troops instantly by using wormholes. This was changed however, as it was later on designed as a weapon to throw entire countries into the wormhole to remove them entirely.
Before the completion of the device a spy was noted to have infiltrated the facility and sabotaged the machine resulting in a explosion. the resulting explosion was immediately followed by the bombing of various allied countries against Japan, to have it be engulfed by it's own Dimensional Weapon.
The resulting bombing opened a gateway to an area in space described as far removed from earth. Tokyo and it's ten million residents at the time were swallowed and presumably dead after. Subsequently Dark Matter had entered earth through the gateway. Along with the dark matter two unknown entities also traversed space and came out of the gateway.
The entirety of the black spot is depicted as being a barren wasteland filled with ruins of cities. Almost all buildings in the black spot are dilapidated or in need of repairs. Vegetation is rarely shown/present in the black spot.
Life in the Black Spot
The general consensus in the black spot is "survival of the fittest". Those who are strong may oppress the weak. Those who are needless are strong and possess powers. Poverty and hunger is prevalent almost everywhere in the black spot.
There is no official governing body in the Black Spots nor law enforcement body. There exist cities within the black spot such as the underground city and the town built for the Black Market. It is most probable however, that they simply practice self governance. Outside the black spot or maybe even their city they have no power. No law is applicable within the black spots, this includes international law and human rights.There exist in the black spot various guilds. The most prominent guild in the black spot is the Mercenary Guild, which Blade and Seto were initially noted to be members of. It has been mentioned that some companies have illegally moved into the Black Spot, making use of its lawlessness and inculpability to any Law, be it national or international.