Ryugu Kingdom

The Ryugu Kingdom (リュウグウ王国) is the country that King Neptune rules over. It includes all of Fishman Island as well as the surrounding areas. It first appeared in Chapter 609.

Layout

 * Further information: Fishman Island landmarks

The majority of the buildings of the Ryugu Kingdom are designed like seashells. They are built on coral reefs. Some buildings are floating in the air with bubbles encasing them. Also, throughout the kingdom are water streams that arc through the air, allowing citizens to swim within them for transport, and with Bubbly Coral as an inner tube, people can float in air as well.

Mermaid Princess
The Mermaid Princess is a legend passed down the kingdom, of a mermaid capable of speaking with Sea Kings, born once every few hundred years. Shirahoshi is the Mermaid Princess of this generation.

Tamatebako
The Tamatebako is a mystical box in the possession of the Ryugu Kingdom, capable of making a person older. Vander Decken IX wanted to use it to age Shirahoshi so he could match her age with his in order to properly marry her.