Mushikago no Cagaster  

Cagaster of an Insect Cage, 虫籠のカガステル, التحول المدمر

In the not-too-distant future, an affliction known as "Cagaster" emerged, transforming people into bugs. The narrative commences thirty years after this illness's onset, in 2125. It focuses on Kidou, a young hero who combats insects.