The school is run by Shinigami, the God of Death himself, as a training facility for weapons and the human wielders of those weapons, the meisters. Each meister has at least one demon weapon companion which has both a weapon and human form. Shinigami created the school as an organization that enforces peace in order to prevent the rebirth of the “kishin”, evil demon gods that nearly destroyed everything by plunging the world into chaos. Human souls that have become evil by straying from the path of humans have a high risk of becoming kishin, so evil humans are constantly being hunted down and killed by the students trained at Shibusen. The ultimate goal of the students with their weapons is to have their weapons defeat and eat the souls of ninety-nine evil humans and one witch, which will dramatically increase the power of the given weapon and thus be capable of being used by shinigami.