The Idolm@ster: Shiny Colors - Hazuki's Shinography summary:

"283 Production" is a place where idols with striking personalities hang out and gather, a tiny yet lively agency that makes them feel right at home.Dealing with phone calls, preparing documents, accounting expenses, and so on... With a job different from "producing", office staff are the ones who support idols who shine.283 Production's office staff, Nanakusa Hazuki. Being a staff, a daughter, and an older sister, the experiences she gathered from her daily life and her feelings shall become the light to help the idols "shine". A new "Idolm@ster Shiny Colors" will begin to unfold──from the perspective of an office staff!