In the year 2163, Mankind was at a financially and technologically peaceful state between the constant conflict against the Bydo Empire. A space project called Project Paradise that had been held back for a long time was finally seeing light.
The idea was to build a Quasi-mechanical Earth by using a bionic computer called "Major", it's purpose was to colonize and create the ideal world.
This plan ended in failure due to the malfunction of Major, the rejection of this bionic computer system was blamed for this failure, however, the actual cause is still unknown.
As a result of this failure, the Paradise Plan became a part of history as it was destroyed by the latest technological weapon known as "LEO".