Hanamaru Biwa

The tenth sister.

Clean, proper, beautiful, reserved, and modest. She is an anachronistic elder sister who lives up to the Yamato Nadeshiko image. She loves old culture and her tone of voice is like that of a period drama.

She is a martial arts expert, with dozens of martial arts skills mastered. However, she is a strict and merciless older sister to her younger brother. Like a nagging grandmother, she worries for the brother but easily goes overboard into "severe scolding mode", even using force. She always justifies herself by saying "It's training!"