Plot
One thousand years after the fall of modern society, Saki Watanabe is born in the tranquil agrarian settlement of Kamisu 66, a society where all humans wield potent psychic abilities. Initially feared by her parents to be a latent, she awakens her powers at age twelve and enrolls in Sage Academy alongside her peers—Satoru Asahina, Maria Akizuki, Mamoru Itou, Shun Aonuma, and Reiko Amano. Unbeknownst to them, the village authorities closely monitor students, eliminating those deemed unstable or dangerous. Erased from collective memory, these disappearances leave no trace; Saki and her friends remain unaware of Reiko's fate.
During an unsupervised excursion, the group encounters a False Minoshiro, a relic from the past that reveals the dark origins of their civilization and the true nature of their powers. Before they can learn more, the monk Rijin intervenes, destroying the machine and suppressing their abilities as punishment for consorting with forbidden knowledge. While returning to face judgment, Rijin is slain by rogue Queerats, and Saki and Satoru are captured. They escape with the aid of Squealer, a member of the Robber Fly colony, who later assists them in defeating their pursuers alongside General Kiroumaru of the allied Giant Hornet colony. Reunited with their friends, Saki restores their powers using hypnotic techniques employed by the village and returns home, believing their transgressions remain hidden.
Years later, Shun isolates himself before vanishing entirely. Saki discovers him in seclusion, learning he has succumbed to becoming a Karmic Demon. Before taking his own life, he reveals the adults' awareness of their past misdeeds. Though memories of Shun fade, Saki and her friends sense his absence. Meanwhile, Mamoru and Maria flee when the village targets Mamoru for elimination, aided by Squealer—now called Yakomaru—who stages their deaths. Saki later dreams of a faceless child warning her against searching for them.
As an adult, Saki works in the Department of Mutant Management, overseeing the Queerats. Yakomaru rises to power, conquering rival colonies before launching an assault on Kamisu 66 with a supposed Fiend—later revealed to be the child of Mamoru and Maria, raised by Yakomaru to bypass the psychological restraints that prevent psychics from harming humans. Pursued and outmatched, Saki and Satoru seek the Psychobuster, an ancient weapon, but ultimately spare the child upon realizing it is no true Fiend. Kiroumaru sacrifices himself by provoking the child's Death Feedback, ending the rebellion.
Yakomaru is captured and subjected to unending torment, though his defiance and claim that Queerats are human unsettle Saki. She later learns the Queerats were once ordinary humans genetically altered to prevent triggering psychic inhibitions. Unable to bear his suffering, she secretly ends his life.
A decade later, Saki and Satoru, now married and expecting a child, look toward the future with cautious hope, believing the world may yet improve for the next generation.
