Originating from the Phantasy Star Online 2 universe, Ulku (also called Ulc) first appeared as a tenacious individual who failed the ARKS entrance exam due to her incapacity to manipulate photons. Undeterred, she joined ARKS as a waitress at Franka’s Cafe, openly aspiring to become a trainee. She maintained a close bond with Theodor, her childhood friend who preceded her into ARKS, often vowing to match his achievements through relentless effort.

During her trainee deployment on Ship Themis, Ulku answered a falspawn assault. Her transport was destroyed, marooning her. While signaling for aid, she confronted a bird-like falspawn using a salvaged rifle. The ensuing explosion nearly killed her, but time-traveler Ash intervened. Rescued, Xiao (in an Auxiliary body) disclosed her survival must remain concealed: Luther had orchestrated her front-line placement to eliminate her and manipulate Theodor.

Ulku faked her death and covertly allied with Xiao and Ash to dismantle Luther’s schemes. She later reemerged publicly alongside Sarah, confronting Theodor. He disbelieved her survival, attacking her as an illusion. Ulku approached calmly, touched his face, and apologized for his anguish, causing both to collapse unconscious. Post-conflict resolution, she and Theodor aided recovery efforts on an ARKS ship, where she reminded him to handle lunch boxes with care.

Ultimately, Ulku ascended to Commanding General and ARKS commander-in-chief, also assuming head-of-government duties for the Oracle fleet. She actively supported Ash’s critical missions, including aiding Matoi’s rescue by providing tank fire against berserk ARKS combatants, directing Theodor to secure frozen enemies while Ash advanced toward his objective.