THE IDOLM@STER.KR is being aired on Amazon Prime. It's a Korean drama based on the Japanese video game series of the same name. The cast includes Sori (CocoSori), Suji and Jane (former THE ARK), and Mint (former TINY-G). Another group on the show consists of Sojin (Nine Muses), Kaeun (After School), Han Hyeri (Produce 101/I.B.I), and Ari (TAHITI).
Thanks for the heads up! I'm watching this right now.