Lady Une serves as Treize Khushrenada's adjutant within OZ, defined by absolute loyalty driving her actions. She experiences dissociative identity disorder, manifesting three distinct personas: a dominant militaristic personality marked by ruthlessness, tactical efficiency, and willingness to employ extreme measures like assassination and colony blackmail; a pacifistic diplomatic personality focused on negotiation and peacebuilding; and a later integrated persona merging both traits after critical injury. Her military persona executes high-profile assassinations, including Vice-Foreign Minister Darlian via a bomb disguised as a makeup kit, and attempts to eliminate Relena Peacecraft. This persona commands OZ's anti-Gundam task force, using missile satellites to threaten colonies for leverage against Gundam pilots. Following Treize's criticism of her brutality, her psyche fractures, causing the pacifist persona to emerge during her colonial ambassadorship. This diplomatic identity publicly advocates reconciliation, opposes OZ's Mobile Doll program, and forms alliances with colonial leaders, while her militaristic self continues covert operations like capturing Gundam scientists and pilots. Conflict between these identities escalates until Tubarov's coup attempt results in her being shot and lapsing into a coma. Upon awakening, her personalities merge into a third state combining military pragmatism with diplomatic ideals. This unified persona steals the Wing Gundam to save Treize from Zechs Merquise during the Libra conflict, subsequently serving as his chief-of-staff aboard MO-II and witnessing his final duel and death. Following Treize's demise, she joins the Preventers organization under the codename "Gold," dedicating herself to upholding his vision of a balanced world order. Her responsibilities expand to safeguarding his daughter, Mariemaia Khushrenada, raising her while preventing exploitation of her lineage. This role continues through the Mariemaia Army uprising in Endless Waltz, where she coordinates Preventer actions against Dekim Barton's attempted revival of Operation Meteor. Her combat capabilities include proficiency with firearms, explosives, mobile suit piloting (notably challenging Wufei's Shenlong Gundam in a Leo), and strategic command, later augmented by diplomatic acumen in her merged state. Her narrative concludes with ongoing service in the Earth Sphere Unified Nation era, balancing operational duties with guardianship of Mariemaia, symbolizing her commitment to Treize's legacy through practical peacekeeping.