Mushikago No Cagaster

at the end of the twenty-first century, a rare disease named “cagaster” began infecting the human race — transforming them into massive insects. two-thirds of earth's population had been devoured by these insects before humanity came to a decision: those that were infected must be exterminated. in the year 2125 — thirty years after the discovery of cagaster — a young exterminator named kidou finds a man dying from insect-inflicted wounds at the edge of the desert near the insects' “cage”. the dying man entrusts kidou with his daughter, ilie, and tells him to seek out the girl's mother.