Unkai

Unkai (雲海, Cloud Sea), known as the Sea of Clouds, is a sea above the clouds. It can be seen from most locations at a great height in the Twelve Kingdoms, such as a kingdom's palace and Mt. Hou. Above the clouds, the Unkai is an actual sea; rain is the water being released to the ground below the clouds.

The world below can be seen through the water. When a new ruler assends the throne a Genbu will swim through the Unkai and create what is called a zuiun.