With all of their assignments completed for the quarter, the R&D division begins their holiday off. When no one has any idea how to spend their vacation, Wilbell appears and convinces them to accompany her on a hot springs trip located near the base of a volcano. At the hot springs, the girls enjoy the water while Logy and Awin set up the tents, during which Logy learns of Awin's dream to travel to the end of the world on his own balloon. Later, the girls are attacked by the Flame Ruler, a fire spirit residing in the springs...