Turii is an island in the World of Aria Te'Laria, to the West of the Eijeek continent. It exists as a way to counteract Ristaccia's influence and its consequences, which in effect, means repairing the damage caused by the Ristaccia war. The Star Children live there, as well the Turii Tree : they are the means to struggle against this force.
Turii is the incarnation of nature, stability, and instinct. Since it is the opposite of any Ristaccia product, nature reigns there wild and supreme, and there is no sign of any sort of culture and civilization. Not even the Star Children are sentient : they are merely instinctive existences, meant to live and die in the endless cycle necessary to compensate the jewel's power. Their death is ritualized in a ceremony called the Panta Rhei that occurs fifteen years after their creation.
The island was undisturbed until the Sazaragi Agency decided to explore it. Their actions ruptured the natural balance of the island ; seeing Malchut drown in the traditional ceremony of sacrifice, Kukaru immediately rescued her and brought her away, perhaps forcefully, to Masinowa.
From then on, all Star Children - including Malchut herself - started to feel, think, develop personalities as well as physical sexes and genders, things they did not possess in order for stability to remain absolute - reproduction being one of the main vehicles of meme. It is probable that all nine of those who were left on the island died on their own, as they are shown as spirits later on in the Epic, more precisely in the Raison d'Être PV.
Turii's power seemed to live on through Malchut, as she was able to invoke the spirits of the Turii Tree and was isolated for purification when she became a target of meme. It is likely that the force of nature that inhabited Turii latched onto Malchut and, in turning her into the Sealer, ensured its survival and its ability to put down meme for good.