A bright and cheerful girl sporting azure-blue hair and pigtails held by two small wooden cubes. She is more 'normal' in contrast to her friends Yuuko and Mai, though she has a very short temper and is prone to tantrums. She has a crush on Kojiro.

Mio is smart and excels in academics, and Yuuko often copies her homework. She likes to draw yaoi in her notebooks but is mortified of it being discovered, often displaying unhuman strength when trying to hide it.