Shioshishio is an underwater village.
Shioshishio is an underwater village and probably the last sea village. This is also the residence of the protagonists: Manaka, Hikari, Chisaki, Kaname and formerly Akari.
The village is protected by the scale of the Sea God, Uroko-sama.
After they've 'received' the news that the world will end in years, they've decided to Hibernate and only wake up after the world had its Ice Age.
Most of the people had fallen asleep after Episode 15, except Chisaki, grandfather of Tsumugu and Akari.
All other protagnists, Manaka, Hikari, Kaname have hibernated, but have woken up five years later.