Even now, the hypocenter is filled with gunpowder smoke and the remnants of what "was" civilization.

Breaking through the outer shell of visitors, "those with the same form but different definitions" appeared. But the same is true of the human race, and those who are called "meteors" are slightly outside the definition of a person.

"Meteor elements" are materials brought by accident in the process of development. While they are a great boon to mankind, at the same time, their poisons poison the body. While many people are dying from meteor elements, newcomers begin to emerge who have adapted to the substance. These newcomers, who possess a new organ called the "meteor elements organ" and wield the ability called "Gear," are the only ray of hope for the human race, which is being overrun by the "visitors.