An established actress of great talent and self-professed star of the Hanagumi, Sumire is arrogant and conceited, perhaps because she was raised as a spoiled brat, with her father and grandfather being good-hearted yet very workaholic. Despite her attitude, she is skilled pilot and highly capable of wielding a naginata, and can sometimes be rather wise. She is a daughter born into the elite Kanzaki industrial clan, whose factory produced the Koubu.