Kazuma moves to the country town of Yamabi Kochou together with Ayumu, his younger brother, due to the latter's weak constitution. On the way to Yorodzuyo, the inn in which they are planning to lodge, run by their father's old friend, they take the wrong bus. When a monkey steals Ayumu's cap, Kochou recklessly follows the animal into the forest, and promptly gets lost. Luckily a beautiful mysterious girl named Ui suddenly appears...