The Mud Whale (泥クジラ, doro kujira) is the ship upon which Chakuro's people live. Two groups of people live upon it: the short-lived thymia wielders, the Marked, and the longer lived and less numerous Unmarked. It is ruled by a council of elders. People of the Allied Empire refer to it as the Failana (ファレナ, farena), most likely taken from φάλαινα, the Greek word for whale. For some unknown reason, the thymia users of the island are much stronger than those of the Allied Empire. The population at the beginning of the series is 513, with 459 Marked and 54 Unmarked.
93 years before the start of the story, a certain group of people from the Allied Empire committed a certain crime and fled on the Mud Whale. Those people were the ancestors of the current population of the Mud Whale. In Episode 5, it was revealed that their ancestors were exiled because they did not want to lose their emotions, unlike those who are affiliated with the Allied Empire.
The leaders of the ship appear to be the Council of Elders, which any Unmarked is initiated into on their 61st birthday. New initiates into Council of Elders are told the secrets of the ship, which the Marked never learn. The Vigilante Force, made up of the strongest thymia wielders on the island, follows the orders of the Council of Elders to preserve peace on the island.
The Mayor of the island, another Unmarked, is chosen by the Council of Elders to serve as a figurehead for the Unmarked of the island. It is unknown if they serve as Mayor until they join the Council of Elders or not.
The regular members of the ship all take turns farming and gathering food.
Clasping of hands - It is customary on the Mud Whale to clasp your hands and dig your nails into your palms in order to avoid showing excessive emotions. Men tend to clasp the back of their hands and women tend to grasp the palms. However, some of the younger Marked have begun to see the practice as old-fashioned and avoid it.
The Great Flying -
Sand-throwing Festival -