Set in Japan in the year 4026, the story unfolds in a post-apocalyptic land whose natural world has been ravaged by a spreading corruption. It follows Emma the Sealer, an eighteen-year-old woman gifted with blight powers that let her manipulate plants to travel across the ruined landscape and battle the creatures that roam it. She is joined by Koo, a stray dog who becomes her steadfast companion on the journey. Together, the young woman and her dog set out across the blighted wilds in pursuit of a single goal: to confront and free the world from the corrupted creature whose taint has poisoned the land, hoping to restore life to a country long consumed by ruin.