Earth

Earth is a planet in our solar system. It is part of the Milky Way.

In Tsinko no Fuko
Earth, specifically Japan, is the home of Kazuhiro Takahashi, Satoshi Kobayashi, Isaya Yoshizaki and Yamura Takahashi.

* SPOILER ALERT*

Dreven Murik and Kotami Matsushina also originated from Earth. They went to tsinko as one being 100 years before the events of Tsinko no Fuko.

* END OF SPOILERS*