My name is Rebel Anne Rae.
and I am the last remaining human alive on planet Earth.
Twenty years from now, the world has been ravaged by environment and global crises, resulting in worsening conditions and a sense of doom for humanity.
In an attempt at revitalization, they turn to the help of robots called 'Mech'.
But when the robots determine that Earth's best chance of survival is the eradication of humanity, people are forced to flee the planet.
And a solitary girl.