Onigawara is a school nurse and enjoys making people to perform cosplay. She is something of a sadist and has a close relationship to Mio Isurugi, to the point that Mio calls her "Michiru-nee". She is shown to enjoy taking pictures of pretty girls especially when they're wearing costumes she created for them. She also knows that Mio, Arashiko and Nao have feelings for Taro, and usually place competitions where he is the prize.
