Cephiro is the homeworld of the peoples of Cephiro. Before the loss of its Pillar, Princess Emeraude, there was such great peace that the natives did not even need to worry about protecting themselves from the elements.
In spite of the peace enjoyed by the natives, Cephiro still had some dangers, such as the occasional monster that would appear and attack anyone. Cephiro has two continents separated by a large ocean, and floating in the sky there are islands covered in giant crystals.
Cephiro is a magical land that can turn almost any person's wishes and desires, even subconscious ones, into reality. Hence why Cephiro is often called "The Land of the Will".
It is named after the Nissan Cefiro (https://en.wikipedia.org/wiki/Nissan_Cefiro).