There are ao many similar series that have many handsome boys while there is only one girl, generally, she is the hero, sush as Uta no Prince-sama, Starry Sky, Brothers Conflict and Diabolik Lovers and a lot of others. In Hakuouki, Chizuru Yukimura disguises herself to avoid any disruption of order in the organization. As matter of fact, she is a pure-blooded Oni (demon).
There are many different anime costumes for Hakuouki Chizuru cosplay, one of the most popular pieces is the simple and beautiful pink and white kimono. The red, black and white western outfit is also in cool and beautiful style. And the blue grey school girl uniform is also quite pretty.