Samurai 8: The Tale of Hachimaru, Vol. 1

Only the most powerful warriors are able to transcend their human bodies and become something even greater—samurai. Samurai carry special souls within themselves and can travel through space as easily as walking the earth. Hachimaru has always dreamed of becoming a samurai, but he's as weak as they come. He's so sickly that he can't even eat solid foods. Being too weak to leave the house may have turned Hachimaru into an expert at video games, but with enough heart, could he become a true samurai?

Volume 1 of the Samurai 8 manga series by Masashi Kishimoto.