CV: Kazusa Murai
Mio is a very energetic and cheerful 5th-graded girl, and she is an activist who is as good as Tomoru. She has excellent insight, and most of the time in the team, she makes a proposal based on Eureka information or discovers something in the middle of a mission. A self-paced and solid person, every time there is something about Tomoru, they quarrel with each other, but in the end, the three of them, including Dai, are on good terms.
Mio is seen as a fifth-graded elementary school student depending on her height in the anime. She has dark rose red eyes and long brown straight hair, with a yellow ribbon bond for her ponytail. For her casual outfit, she wears a bright yellow and orange vest, dark bluish skirt with sky-blue panties and deep navy stocking with bright and baby pink sneakers.