Droxine was the daughter of Plasus, the high adviser of Stratos on the planet Ardana. She lived a privileged life in the cloud city above the planet's surface. She, like her father, believed the Troglytes to be inferior beings.
She appeared to be quite interested in Spock, who uncharacteristically referred to her as "a work of art." Spock became attracted to her in turn, and discussed the Vulcan mating ritual pon farr with Droxine when James Kirk shouted; they found him with Vanna who intended to take him as a hostage. It was then when Vanna revealed herself as a Disruptor. When she was taken by the guards, Droxine explained to Kirk and Spock that the Troglytes are not accustomed to light, warmth or logic, and things are supposed to remain as they always had been.
Later she was seen present during the interrogation and torture of Vanna.
While her father banned Kirk from returning to Stratos, she explained him how she longed for Spock. After the issue with the zenite was settled when Kirk traded with Vanna some filtered masks, Droxine told Spock that she preferred the less technical term "Protectors". She then expressed her wish to not be confined in the clouds, and her desire to visit the mines of Ardana, and even Vulcan. (TOS: "The Cloud Minders")