Mysterious rifts appear simultaneously in the skies above every country. Three days later, the first meteorites fall, releasing the "zombie virus" and "superpower awakening factors." Zombies mutate far faster than in science fiction, and after 72 hours they can evolve into agile and powerful creatures that pose a threat. About 20% of the survivors awaken supernatural abilities, most of them at D or E rank, while the protagonist is the only one at SSS rank.
