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 actions and their consequences, and, consequently, to repair the damage caused by the Ristaccia war. The Star Children live there, as well the Turii Tree, as the means to struggle against this force. Turii is the incarnation of nature, stability, and instinct, and since it is the opposite of any Ristaccia product, nature reigns there wild and supreme, and there is no sign of any building, of any sort of culture - not even the Star Children are sentient, as they are merely instinctive existences meant to live and die in the endless cycle necessary to compensate the jewel's power. The ceremony in which they willfully die is called the Panta Rhei.
The island was undisturbed until the Sazaragi Agency decided to explore it. Then, Kukaru's actions broke the natural balance present there ; seeing Malchut drown in the traditional ceremony of sacrifice implied in the cycle, he immediately rescued her and brought her away, perhaps forcefully, to Masinowa. From then on, all Star Children - including Malchut herself - started to feel emotions, sensations, develop personalities and, more basically, genders, things they did not possess in order for stability to remain absolute. 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.
But Turii's power lived on through Malchut, as she finally acomplished the reason of its existence.