It hard to search iDOLM@STER series.

why it is not separated iDOLM@STER series?
It is over the 4 series.

THE iDOLM@STER
THE IDOLM@STER CINDERELLA GIRLS
THE iDOLM@STER: Shiny Colors
Gakuen iDOLM@STER

lovelive series are have been separated.

so I suggest add the tag iDOLM@STER series.