It all began quite suddenly. Akihito, who appears human but is actually half yomu with the power to quickly heal himself, sees a freshman girl who appears ready to jump from the school rooftop. The girl, Mirai, who has the ability to manipulate blood, which is unique even among members of the spirit world, continues to fight her isolation. Akihito decides at that moment to save Mirai, but disturbing events soon begin to unfold.

The battle is over, and they can go about their normal lives now... or so they thought. With no time to rejoice after miraculously saving Mirai from Beyond the Boundary, Mirai lost all her memories. Akihito, now a high school senior, starts to avoid Mirai thinking it’s for the better. Not aware of Akihito’s feelings, Mirai tries to get closer to Akihito. Then, someone who knows of Mirai appears in front of the two. With Akihito’s troubles in vain, Mirai once again sets forth on a battle that forces her to look within.