knights of sidonia/Sidonia no kishi [Manga]

The story follows the exploits of Nagate Tanikaze, who lived in the underground layer of Sidonia since birth and was raised by his grandfather. Never having met anyone else, he trains himself in an old Guardian pilot simulator every day, eventually mastering it. He emerges to the surface and is selected as a Guardian pilot after his grandfather’s death with hope he can defend Sidonia from the Gauna’s attack using all the combat expertise Nagate learned from him.