In the 21st century, people's affection for cats has deepened to the point that almost everyone keeps one as a companion. Yet, intensive breeding of felines produced an exceptional specimen that harbors a peculiar pathogen. The ensuing outbreak—named the Nyandemic—converts any human who touches an infected cat into a carrier.
Kunagi, a man stripped of all his memories, is compelled to abandon his shift at a cat café. He is accompanied by the siblings who manage the establishment, Gaku and Kaoru, along with a patron named Tanishi. Gaku reveals that he is already infected and urges Kunagi to safeguard his sister. After confronting the peril directly, the remaining trio sets out to find a means of surviving the very creatures they cherish.
Despite governmental attempts to curb the feline menace, the Nyandemic spreads unchecked. The prospect of human annihilation looms with each passing hour—yet Kunagi, Kaoru, and Tanishi refuse to relinquish their humanity without a struggle!
