Medlock commands the Deague warship Kunrun, relentlessly pursuing the Union vessel Libertad throughout the conflict. As a high-ranking officer within the Deague military, she oversees anti-Union operations and technically outranks Ralph Werec, though she increasingly defers to his expertise.

Her strategic judgment erodes due to a romantic entanglement with Ralph Werec, granting him unrestricted access to ship systems and autonomy despite his defector status. Crew members frequently observe her in casual attire within her quarters, where her relationship with Ralph remains visibly undisguised.

Subordinates including Lt. Colonel Barrow challenge Medlock’s trust in Ralph, voicing suspicions about his loyalty and hidden motives. She dismisses all warnings, prioritizing personal attachment over tactical prudence. This pattern holds until Ralph unveils his plan to exterminate all human adversaries, including former Deague allies.

Confronting his betrayal, Medlock triggers the Kunrun’s self-destruct sequence to trap him aboard. Ralph overrides the controls, seals her inside a freezing shower room, and commandeers the vessel. He deliberately crashes the Kunrun into the Libertad, killing Medlock during the collision.

Her arc transitions from military authority to manipulated figurehead, culminating in her death as Ralph executes his genocidal vengeance against humanity.