--- Red Nightmare --- "If Menou-chan is going to die, then isn't it better for the world to perish?" Akari and Momo have disappeared. Confused by the betrayal of her trusted juniors, Menou begins to pursue the two while grappling with the voice of Sahara echoing from the scriptures. Meanwhile, Akari and Momo continue their escape from Menou, repeatedly clashing despite their hopeless incompatibility. A forbidden partnership between an otherworlder and an executioner's assistant. However, for some reason, the two, who are "Menou-first" advocates, start a rigorous training regimen led by Momo to strengthen Akari during their flight—? Intersecting otherworlders, "The Fourth," and the first class. Will hope or despair await the girls? This is the story of a girl who kills another girl, in the fourth volume stained red!