Saya Otonashi (音無 小夜, Otonashi Saya?) was "born" in 1833 from one of two cocoon-like objects taken from the belly of a chiropteran mummy, the other cocoon containing her sister Diva. Both are kept at the "Zoo" by Joel Goldschmidt, where Saya is treated as his daughter and Diva, who is left nameless, is confined to a tower. Saya does not learn about Diva's existence until 1863, when she hears Diva singing and finds her locked in a room at the top of the tower.
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