Is Neru a fan-made Vocaloid or not?

She's a Voyakiloid, so yes. She's fan-made.

Akita Neru is a Boukaloid. She is not official, though Crypton, the creators of Miku, Rin, Luka, etc. recognizes both her and Yowane Haku, a Voyakiloid. They are not official Vocaloids, but they are in a few official video games, like Project Diva.
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yes she is fan made