Hester Gallop was the daughter of the President of the United States of America. Having witnessed her father's assassination in the hand of dissidents, Hester became determine to continue her father's work of establishing the Neo United Nations and the Human Army. She eventually became the first Secretary-General of the Neo United Nations in 2115. Under her watch, the two organizations aggressively pursued the eradication of Festum, taking inhuman actions conducting nuclear strike at Japan in 2118, or killing all humans on Wadatsumijima to recover its Core, which would become the Prometheus Core. In Dead Aggressor:

Spoiler

Hester Gallop had a minor role in Dead Aggressor and was first seen at the end of episode 4, as the Neo U.N. search plane that Kazuki saves from the Festum reports Tatsumiyajima's location. Five years before the series started, she accepted Mitsuhiro Bartland and Youji Hino after they deserted Tatsumiyajima, in exchange for they to develop the Human Army Fafners. She witnessed the Operation Heaven's Door, which was a success in that most of the North Pole Festum was eliminated, and the Human Army was able to restore a satellite in orbit.

In Exodus:

Spoiler

In the aftermath of the Festum's attack on Hawaii, Hester ordered the ROE Alpha protocol to be carried out regardless of the civilians and Human Army personnel presented on the battlefield. She later oversaw the movements of the refugee convoy leaving Srinagar, sending their location to the Aviator through the Prometheus Core so that the Festum would destroy the convoy. After Maya Toumi was captured, she was brought before Hester, who declared her intention of having Maya piloting the Mark Raison. She also showed a degree of fondness toward Maya because the girl reminded her when she was still young. Hester wished for Maya to join her in the quest to wipe out the Festum on Earth. The Prometheus Core later betrayed Hester and took control of the puppets. It also made a deal with Dudley Burns, who would control Human Army force as its proxy. Hester however was able to escape from the island, and was last seen watching the Fourth Operation Azure unfolded.