Far away in the ocean, there is a hidden island, covered in a fog, like a ghost. According to a legend, there live monsters, who guard berries and mushrooms that grow on the Island. Approaching the Island is forbidden… One day a boy accidentally finds himself on the Island, facing all its mysteries. At first monsters were friendly, but the boy turned out to be a devil. Monsters got tired of his antics and decided to send him back. Will the boy be able to return home safe and sound and keep the secret of the Island?