Year 20XX...
It was a sunny day that time when everything is peaceful, no wars but there're some conflicts between nations but war never broke out, crimes constantly happens in every city in every continent but it's fine since some of them were successfully captured... or killed.
Actually the earth we lived in is not peaceful as the author says, different crimes constantly happens, some have been killed, murder, rape, etc.
Many things were happening in the earth but of course not everything is bad there's also many people who play as a guardian, that helps and protect the citizen of their city (I think some of them are.)
Some are policeman who capture and stop the crime from happening, some are doctors who help people that were injures. A firefighter who help peoples that in some places that were lit on fire, etc.
But we are not here to talk about the profession of the people, but we are going to talk about the 'being' who is an overseer of everything, the being who puts humanities lives on the line, the one who created the 'Chaotic War of Invasion'.
They call themselves 'Celestial', the being who gave everyone a system, where people can have a primary and secondary job, a system where people can see the skills and talents that they have.
People thought that it was a blessing, a great gift from the almighty god, that's why they strive to become the strongest, but little did they know that a great danger was approaching, it was so great it can cost the extinction of the human race.