Like the title says, through all the fighting, killing, and bloodshed, this story's primary theme is friendship. It's about people who take separate paths through life and the strength of their bond is tested over and over again. How far will you go to save a friend? How much can you endure before you step in to protect someone? Whose orders are you willing to disobey to keep from hurting someone you care about? When does it stop? When will it end? These questions don't have to said. It's there, through this entire script. And what I liked about this show is that they didn't take the traditional cliched route to tell the story. It kept it interesting and keeps you wondering to the end.