C84 Who Is the Murderer and What Is His Purpose

Was there really someone in the martial arts world who had this kind of martial arts? She had also seen this martial arts technique when she was in the "New Dragon Gate Inn". It would instantly remove flesh and blood. The speed of her blade technique was so fast that no one would be able to fight back. If she could, she would like to believe that it was a bug's doing, not a human being