Jaiko is Gian’s younger sister who would have been Nobita’s wife in the future had Doraemon not intervened. She first appeared in the first story, before the introduction of Gian.

Her name Jaiko is usually considered a nickname, but Fujiko never gave her a real name.
Jaiko goes by her amateur mangaka pen name Christine Goda (Kurisuchīne Gōda?), and sometimes submits her stories to publishing companies for prizes.

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