The creation of the Template:Explicit was done at the request of commenters. So I am wanting to know does this template need to be on any other Song article pages?
This wiki pretty much accepts every Vocaloid song that is available and those willing to create a page for it, or you can help out the Vocaloid Lyrics wiki.
Update Jan 12, 2013
The templates have been split, so now there is Explicit and Questionable. They bot go into the same category. :Category:Lyrically Questionable or Explicit songs
Separated categories May 2014 Lyrically questionable songs and Lyrically explicit songs
Due note that the templates should be used if the content of the song appears explicit / questionable. Some songs may contain profanity, innuendo, or mature subjects, however, this doesn't always require a notice template.