Damn, I can't believe she got out of the classroom with most people seeming to believe her. This is definitely a very strange manga, and I really don't know where it's going, but I wouldn't be super surprised if "Black Rose-sama" is still alive.
Seems like her voice has some charm ability...? Maybe her saying her name in that park gave Kyouka the push, since she said her voice was like hypnotic or something?