Kasane Teto is a 2ch-born character, who was created as a fake "Vocaloid" initially.
Following the rising popularity of Hatsune Miku, vip@2ch users collectively planned the troll "new Vocaloid release" for the April Fool's day of 2008, and fake demos were posted on Nicovideo. The illustration was created by Sen and the songs were sung by Mayo Oyamano.
After the troll, Mayo's voice was recorded for Vocal synthesis tool UTAU, which was personally developed by Ameya/Ayame. Soon many professional and amateur musicians started to compose songs for this newcomer, and Teto established popularity both on Nicovideo and YouTube.
Kasane Teto is not a fake diva any longer. The popularity led to 3D models, figurines and many illustrations by fans. Furthermore, the regular updating of the voicebank and UTAU platform has made Teto one of the comparable characters to Vocaloids.
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