Ten years have passed since the creation of the Lightless Realm, and the city of Kukujicho becomes more desolate as people's fears increase. Akashi Saginuma, an elite student attending Kukunochi Academy, gets called out by his teacher along with his amiable friend, Iwato Namito. There, they are informed of a "pilot training course" that only the most outstanding of students become selected for.

"Those who hear the Corpse's song will die a mysterious death within nine days." As if that rumor became truth, an incident happened before Akashi and his class. Emiru and Mahmu head over to the ruins of a hospital in order to confirm the other rumor that "the Reaper" -- something that supposedly can defeat the Corpse -- was dormant there. And there, they meet Heito Isaku, another one who was chosen to be part of the pilot training course.

"The Reaper" was something created in order to defeat the Corpse. Akashi starts training as the pilot for "the Reaper," but with excessive stress, he cannot hide his mounting frustration. Meanwhile, Sasame Izuriha, the last of the pilot candidates, finally transfers into class. Akashi finds that Sasame is somehow on his mind and tries to talk to her...

Akashi and the pilot candidates were dropped down onto a deserted island for mock investigation training in uncharted territory. While one condition for them to clear the mission was for "all members to gather in one location," Iwato and Raika fear the danger that Heito, who landed on the deserted island earlier than the others, possesses. While the candidates are enveloped in anxiety and terror beyond words, it was Sasame's singing voice that guided Akashi and the others.

Synchronization of thought between the pilots is necessary to control a MA-Vess... Heito and Emiru, showing high synchronicity, are involuntarily paired up for field training near the Lightless Realm. However, as if it was reacting to the terror Emiru hides deep within her heart, the environment becomes surrounded by an abnormal atmosphere. Over time, Heito's insanity corners Emiru, forcing a situation where there was no turning back from.