A high school-age girl who loves her older brother Jun'ichiro Tanizaki. She has a high intellect, which she studied with Dazai Osamu, and she also has good deduction. She has agility and stamina that is not comparable to the endurance of an ordinary person - even though Naomi doesn't use powers, she has tremendous stamina for a normal human, able to survive near-fatal serious injuries from Higuchi's firearms after covering her brother with her own body one day.