Because he tries to defend himself against his bullies, Lazuro is tied to a tree with a cursed staff. When he wakes up, Lazuro has been transported to another world full of beasts. In this place, only a few people still live on the back of a giant dragon turtle. These people live by hunting beasts with a tool called the Mythbreaker. It turns out that the cursed staff bound to Lazuro is a rare plant Mythbreaker. Lazuro has no idea how to get home except with his cursed staff and a tree that reaches into the sky, the Tree of the World. Can Lazuro find the clue to return to his world?