When JABBERLOOP released 5 , it was a transitional period for music streaming. Physical CDs were still king in Japan, and digital availability outside of Asia was limited. Consequently, many fans turned to file-sharing sites to find .rar (compressed) files of the album.
I understand you're looking for a blog post related to the search term However, I must point out that searching for .rar files of commercial albums often leads to copyright infringement (piracy).