
The dark fantasy follows a high school sophomore named Akihito Kanbara. Although the boy appears human, he is half Youmu and invulnerable to wounds because he can heal quickly. One day, Akihito meets freshman Mirai Kuriyama when it seems she is about to jump from the school rooftop. Mirai is isolated because of her ability to manipulate blood, which is considered heresy among members of the spirit world. Disturbing events begin to unfold after Akihito saves Mirai.






When this seemingly normal boy meets a bespectacled girl on the roof of a school building, she leaves one hell of a first impression.
Mirai goes after a youmu with a little help from Akihito, hoping to make it her first kill. Later, they hear about a menacing new monster on its way to town.
The Hollow Shadow creeps ever closer to town. While all other spirit warriors go into hiding, Mirai is determined to take it down.
Mirai and Akihito seem to be trapped in a neverending labyrinth by the Hollow Shadow. However, defeating may only be the beginning.
Mirai takes a harsh punishment for going after the Hollow Shadow. She's forced to take a part time job, but learns more about herself in the process.
A special youmu with a penchant for pretty girls gives Mirai a tough time, so Akihito enlists the Literary Club for support.
Akihito finds a weakened Sakura and can't help but assist her. However, later on, Sakura confronts Mirai, seeking vengeance.
The Calm, a time of fear for all youmu, is fast approaching. As the clock strikes midnight, all youmu become weakened, and thus, become easy prey.
Akihito loses control and his youmu side awakens. Mirai, and those close to Akihito, are faced with the hardest decision of their lives.
Mirai succesfully stopped Beyond the Boundary, but at a great cost. The truth behind Mirai's past is revealed.
Mirai's battle with Beyond the Boundary rages on in a new dimension, while Akihito tries to figure out how to bring her back.
Akihito reunites with Mirai inside Beyond the Boundary. Meanwhile, the Nase family fights a different war on the other side.