Takao

Takao is the Mental Model of the Fog Ship: Takao-class Heavy Cruiser, from what her name suggests. After a failed effort to defeat I-401, she defects and wishes to make Gunzou her captain.
Originally, Takao was rather arrogant, haughty and narcissistic as well as prone to be a bit overdramatic. After she was defeated by I-401, she spent some time around humans, thinking of the ways to improve herself.

She later joined the Blue Steel Fleet and changed her ship colour to blue.

In the anime version, she gives up her physical form to rebuild I-401 in order to save Gunzou. At the very end, she regains her physical form.