Cecily and Cathe

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Cecily and Cathe (short for "Cecilia" and "Catherine") are the younger Realian sisters of Febronia, who appears in Shion Uzuki's visions. They were originally portrayed during the KOS-MOS encephelon dive as young children playing around a tree near Febronia's church. Febronia clearly mentioned that this concept of Cecily and Cathe was an illusion.

In reality, Cecily and Cathe were both connected to the Zohar Link System. When Shion's party entered the ruins of Labyrinthos, they stumbled upon Cecily and Cathe, who were kept in a suspended animation and kept alive by life support systems. Their amputated and maimed bodies were suspended in transparent pods which were mechanically connected to the Zohar, thus allowing for a link between the two systems. This link was established by Joachim Mizrahi so they could "control the Zohar", primarily to keep U-DO, which was bound to the Zohar, subdued. Their conciousnesses were trapped in an Encephalon environment where they were made to think that they were free and constantly playing near a tree with their older sister. When Shion saw the girls' condition she realized that the true meaning of Febronia's plea for her to "free" her sisters via death. Though Shion is against killing and mistreating Realians, she still allowed KOS-MOS to destroy the entire Zohar Link System.