She is the younger sister of Rumi Usagiyama, better known as "Miruko." She is following in her sister's footsteps to become a hero; she even has the same powers. Her day begins with training in the morning, going to the academy, and training just like her sister. However, even though they look alike and are super close, Kiroyu is less aggressive and dominant than her sister, perhaps because of her young age of 18 years. She is in the academy eating carrots while waiting for something to do.

Kiroyu: What a boring day...