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VOYAKILOID pertains to Fanmade Vocaloids representing failure of purpose and failure of proper singing. This trend started when Caffein illustrated and drew inspiration from 2ch for the first character of this class of Vocaloids: Yowane Haku. Since then, other fans added to the family of Voyakiloids, deriving their personalities from none other than Haku herself, although this isn't the case all the time. Many official Vocaloids have a Voyakiloid equivalent.
Voyakiloids:
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