Kuromukuro

During a summer camp, 15 children, 8 males and 7 females, find a grotto by the sea. Deep within they discover working computers and some electronic equipment, and later the owner, a man called Kokopelli. Kokopelli claimed to be a programmer working on a brand new game, in which a large robot has to defend the Earth against fifteen alien invasions. He persuades the children to test the game and sign a contract. All but one of them signs; barely a moment later they mysteriously awaken on the shore believing what happened was just a dream.

The year is 2307 A.D. Although fossil fuels have been depleted, humanity has obtained a new source of energy to replace them, in the form of a large-scale solar power generation system based on three huge orbital elevators. However, the benefits of this system are available only to a handful of major powers and their allies. In this world of never-ending conflict, a private armed organization appears, dedicated to the elimination of war through armed force. Its name is Celestial Being, and it is in possession of "Gundam" mobile suits.

The future’s looking bleak. It’s a good thing there’s a new sheriff in town. Her name is Jo and she’s an enigma even to herself. Alongside her partners Sei, Amy, and Meg, Jo fights for the citizens who can’t defend themselves. Confronting corruption and twisted science, these gals are on fire—and they’re the best chance the wounded city’s got.

Renton Thurston desires to leave his home behind and join the mercenary group known as Gekkostate, hoping to find some adventure. When a robot crashes through Renton's garage the meeting sparks the beginning of Renton's involvement with Gekkostate as he takes off alongside the young girl Eureka as the co-pilot of the Nirvash.