Naoko is extremely blunt and generally quite selfish. She is commonly referred to as 'the human calculator' for her skills as the Ultimate Accountant. She is dull and hateful in a way that breeds both tension and comedy, and she refuses to allow any of her classmates to make a fool of her. She has a narcissistic core philosophy: always watch out for number one.

Her voice should be mid to low and deadpan, though she is quick to scream or yell in anger when frustrated.

By popular demand, the canon voice that she is most similar to is Maki Harukawa.