Shirakawa Mikuri

"It's all right. Because I'll protect you, Hayato-kun."

Hayato's cousin and classmate. She has an older sister who is one year older than her and attends the same school, Shirakawa Momoyo.

Adorable like a small animal, an airheaded beautiful girl, even in her class, she has many fans, both boys and girls alike. However, if she becomes too airheaded and dangerous, they would act as her protectors and keep her away from anything ecchi.

When she was young, she was attacked by a stray dog, but Hayato came to her rescue. Since then, even though she had not seen him for many years, she continues to think of him wholeheartedly.

When donning a battle suit invented by her sister Momoyo, she transforms into a Heroine of Justice "Marron Branche". In this form, she often acts and says things that could not have possibly came from her usual airheaded beautiful girl personality, and when she reverts back, after a while, she would look back on herself, extremely embarrassed and alone in agony.