Mushi-narrative uta's takes place in the not-too-distant future. Strange insect-like monsters known as "Mushi" began to appear ten years before the story's start. The Mushi may eat people's dreams and ideas in exchange for extraordinary powers. At the end of episode one, protagonist Daisuke "Kakkou" Kusuriya meets Shiika Anmoto, a young girl. Over time, the two become extremely close. Shiika, however, is an escapee from GARDEN, a hidden prison where individuals possessed by the Mushi, known as the Mushitsuki, are imprisoned. The Special Environmental Conservation Executive Office, GARDEN's military force, assigns its best assassin to find Shiika. They are met with opposition by the Mushibane rebel organization, commanded by the mysterious "Ladybird."