I'll take a shot at translating the story :
"Long ago, the gods created a magical floating continent known as Midiarias.
The people of the world lived in peace, until one day when a Demon King appeared. The gods tried to protect the world from the Demon King, and so a long war was fought. Those who worshiped the gods were given magical powers, to fight off the demons that the Demon King would summon. But with each passing day, the demons would cover the world in darkness more and more. When the people were beginning to lose hope, a lone warrior came floating down from the continent of Midiarias. In their hand, this warrior held the Star Key, which contained the power of the stars. With the help of the gods and this warrior, the people regained hope.
The Demon King was finally sealed away with the Star Key, and the war ended. The warrior disappeared shortly afterwards. The people called the warrior the Hero of the Stars. Since then, people who would fight to protect Midiarias (much like the Hero) were referred to as Guardians of the Stars. It is believed that the Hero of the Stars would return if the Demon King were to reawaken.
That is the legend that is still told. Even today, the memory of the Hero of the Stars lives on in the minds of the people. The world was peaceful once again.
And then..."
The game's protagonist is a human named Wanda (not sure about the gender) who obtained the Star Key somehow. Wanda is a child that likes to joke around a lot, and uses the Star Key as a weapon.
