Okay, well... these guys don't have a thread, so here's for the fans of the minor characters!
Minori Ishikawa （石川 実）
CV: Riza Hayamizu
President of 876 Productions.
Mai Hidaka （日高舞）
CV: Ryoka Yuzuki
Super idol diety, won Idol Ultimate and was an S Rank idol... then she had Ai, and retired at like... 15.
Manami Okamoto （岡本 まなみ）
The unfortunate, luckless manager of 876 Productions.
Cineria （サイネリア）, real name Ayane Suzuki （鈴木彩音）
Age: 18
CV: Yurin
Net idol, and Eri's friend. Considers Eri her superior in the ways of the net idol, and is stunned by her decision to take her idolness to the real world. Goth.
Reiko Ozaki （尾崎玲子）
CV: Yuu Asakawa
Eri's Producer, freelancer, and pushes her way straight into 876.
Satomi Konnou （近藤 聡美）
Reiko's old associate.
Yukio Igarashi （五十嵐幸男）
Director of the Idol Classic Tournament.
Yumeko Sakurai （桜井夢子）
CV: Sayuri Yahagi
Ryou's rival that somehow starts to hang out with him. Known for her candies of vocal chord busting flavor, apparently calls it Malicious X, which can kill small wildlife and generally ruin the environment.
Souichi Takeda (武田 蒼一)
CV: Tatsuhisa Suzuki
Hosts the television show, "Old Whistle," which to date has only had one major idol appear on it: Chihaya Kisaragi.
