Hanasaki Tsubomi, Hino Akane, Kenzaki Makato, and Aino Megumi are all voiced by Japanese Pop Idols. Tsubomi's voice actress is Mizuki Nana. Akane's voice actress is Tano Asami. Megumi's voice actress is Nakajima Megumi. Makopi's voice actress is Miyamoto Kanako.
(Fitting for Makopi, since she is a idol in the series)