|Played by||Mikako Ichikawa|
Natsuko is a young woman standing at average height usually seen in a dress suit and glasses. She has black hair tied in a ponytail and has dark eyes.
Natsuko is serious minded individual who focuses all of her attention on her cases, never even smiling and is cold to others even her own subordinates. This is also shown in her apartment where it is rather dull and appears to be unlivable shown by the dying plants. Whenever someone interferes with her case (mostly Honey), Natsuko often tries to get them out of the way either through arrests or other threats. Meeting Honey however, causes her to warm up and become more supportive encouraging Honey not to give in to despair.
As part of her training Natsuko is adept in firearms, usually a small pistol she carries with her. She is also a keen investigator able to figure out Panther Claw's intentions for the I-System.
Natsuko and her squad chased down Gold Claw who abducted Dr. Ryo Utsugi. While put in a tight spot, Natsuko was saved at the last minute by Cutie Honey who fought off Gold Claw. Natsuko tried to arrest her for interfering but was interrupted by Seiji Hayami who she also arrested but Honey escaped. Natsuko was reprimanded by her superiors for letting Gold Claw get away so Natsuko decides to investigate further by looking into a connection between Honey and Panther Claw by speaking with Dr. Utsugi. She follows Honey who was disguised as her and Seiji onto a monorail where she attempted to arrest them but was nicknamed Nat-chan to her chagrin.
Following Honey into her workplace they are ambushed by Cobalt Claw who attempted to choke them. As Honey was enraged that Panther Claw killed her father Natsuko managed to calm her down after Cobalt Claw was burned. With Honey out of power, Natsuko took her to her apartment. When Honey woke up, she told Natsuko her origin and demonstrated her I-System by bringing one of Natsuko's plants to life. Natsuko threw Honey out feeling that her action disrupted her professional environment. Natsuko was later demoted to a traffic cop after her superiors blamed her for Panther Claw's outbreak. Depressed, she went out where she encountered Honey and Seiji and decided to stay with them at a karaoke spot where she passed out after getting drunk. Nat-chan and the rest found invitations from Panther Claw to the Jill Tower.
Natsuko knew it was a trap but went with Honey up the tower to rescue Dr. Utsugi, providing Honey cover as she fought the remaining Big Four. Natsuko during the fight with Black Claw had made a deal with Sister Jill to release Dr. Utsugi. Jill in turn used Natsuko as bait in order for Honey to assimilate with her in order to gain the nanomachines from the I-System. While Honey agreed, Natsuko shot a bullet at Honey's choker causing a flash that turned Jill into a seed. With Panther Claw defeated, Nat-chan along with Honey and Seiji found their own detective agency.