Beyond the Boundary

One day, high school student Akihito Kanbara instinctively goes to save his fellow schoolmate, Mirai Kuriyama from committing suicide. Following his pleas, Mirai suddenly stabs Akihito with a sword formed out of her own blood and is shocked to discover that Akihito is an immortal "half-youmu"—the offspring of a supernatural creature called a youmu and a human. After learning that Mirai is a Spirit World Warrior (異界士 Ikaishi?)—specialists who protect humans from being affected by youmu—and the last surviving member of her spirit hunting clan, their lives become intertwined as Akihito seeks to help Mirai gain the confidence to kill youmu so that she may stop attempting to kill him as practice.