Naomi, a member of the Hosino Tribe—anthropomorphic cockroaches inhabiting a human bachelor’s apartment—is pledged to marry Ichiro, a cautious tribesman unable to fly, whose subdued nature strains their bond. Drawn to Hans, an injured outsider from a militant roach tribe battling humans in a neighboring apartment, she abandons familiarity to pursue danger and passion. Her journey into hostile territory exposes her to human retaliation, near-death in a roach motel, and surreal encounters like conversing with sentient waste. Returning home, she masks her ordeal with Hans, feigning memory loss to shield Ichiro.

When the bachelor’s girlfriend launches an extermination campaign, Naomi’s grandfather discloses her unique resistance to toxins, a safeguard she genetically bestows on her hybrid offspring. Surviving assaults—including a botched raid led by Hans’s tribe—she becomes pivotal to her kind’s endurance. After her tribe’s eradication, Naomi, now the lone survivor, births a brood combining Ichiro’s lineage and Hans’s militant vigor. These offspring, immune to pesticides, abandon dependence on human habitats, forging their own path. Her evolution from naivety to hardened resilience underscores her transformation amid relentless threats, cementing her legacy as both survivor and progenitor of a self-reliant generation.