The song used for the video is titled "Atashi Ponkotsu Android" and a part of its lyrics mentions "hadaka ni nacchao kana", where the word "hadaka" can mean nudity in Japan, although in the original lyrics it means honesty. Nonetheless, the audacious fan changed the lyrics so that the song was only about being naked (though it mostly repeats the same line).
The original video uploaded to the Japanese platform Niconico Douga implemented a mosaic censoring of the idols' private parts (even though they are not really naked), perhaps to further focus the concept of the song.
A version without the censorship filter was also published shortly after.
The videos also made use of some voice modulation, as the creator took the sounds produced by each girl and rearranged them to produce their own lyrics. The uncensored version secured significant attention on the platform, getting more than 37,000 visits in just two days and reaching the top position within the #IdolMaster hashtag.
On the other hand, the series The Idolmaster Cinderella Girls had thirteen episodes and was produced by the studios A-1 Pictures, under the direction and scripts written by Noriko Takao, and originally premiered in January 2015. A second season of twelve episodes it was released in July of the same year.
Source: Niconico
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