Akaboshi Bisco is a hotheaded “Mushroom Guardian” who runs through the Rusting Winds, which rusts all it touch and brings death to humans. In order to save his master, he embarks on a journey to find the “Rust-eater”, a mushroom that is a cure-all to the rust. Together with the beautiful young man, Milo as his partner, Bisco goes on an adventure filled with ups and down.