Japan has become a wasteland devastated by the Rusty Wind which causes all things to rust away. A suspicious looking priest visits a checkpoint all alone, yet on his back rests a bow priests wouldn't use.
Meanwhile, Milo, a doctor running a clinic in the town of Imihama, is researching new medicines in secret in order to save his older sister, Pawoo, who's being corroded by the Rust. But that day a stranger appears before him...
Pawoo! They're here! The Mushroom
 Keepers! On Karakusa Street!
!باوو! لقد أتوا! رعاة الفطور! في شارع كاراكوسا
Pawoo! Auf der Karakusa-Straße
ist ein Pilzhüter aufgetaucht!
¡Pawoo, el Protector de Hongos
está en Karakusa!
¡Pawoo, el Protector de Hongos
está en Karakusa!
Pawoo ! Un gardien est apparu
sur Karakusa !
Pawoo! Sono qui! 
I Custodi di Funghi! Su via Karakusa!
Pawoo! Eles estão aqui! Os Guardiões 
de Cogumelos! Na rua Karakusa!
Пау! Там и правда грибной страж!
На улице Каракуса!