Leader, alias Iizumi Rita, commands the four-member Scavenger group in Academy City. She sports short red hair and constantly wears a distinctive white flu mask marked with two dark crossed hands. Her typical outfit consists of a short-sleeved shirt, shorts, mismatched black tights, and a backpack. A traumatic past involving an abusive teacher fuels her deep resentment towards educators and "teacher's pets," a shared experience binding Scavenger together. They believe eliminating such figures delivers justice. As the group's strategist, she manages her teammates' aggression and actively seeks promising recruits, even attempting to enlist the adversarial Accelerator. Her Level 3 esper ability, "Predator," allows her to track targets through Academy City's surveillance cameras, communication networks, and electronic devices. This power is crucial for Scavenger's operations, identifying objectives and monitoring opposition. During the Necromancer Arc, Scavenger accepts a contract to eliminate the Disciplinary Action (DA). After destroying DA forces and inadvertently killing Anti-Skill personnel, Leader confronts Esther Rosenthal and Hitokawa Hasami protecting Yomikawa Aiho and Misaka 10046. Recognizing Aiho as a teacher intensifies her hostility. Accelerator intervenes, incapacitating her teammates; Leader panics upon identifying the top-ranked Level 5 and loses consciousness from terror. In the Dream Ranker Arc, Leader directs Scavenger's pursuit of Kuriba Ryouko's robotic doppelganger to regain standing. Locating it at Shinasame University, she mocks its desire for humanity, provoking it to break her arm during escape. Injured, she encounters Misaka Mikoto, deceitfully claiming Scavenger belongs to Judgment and providing a fake armband. To maintain the ruse, she gifts Mikoto Gekota-themed communicators and helps redirect the doppelganger to an abandoned warehouse. There, she exploits the confrontation to coerce their employer into approving payment. Despite this, she later orders her team to rescue the falling Ryouko and arranges medical aid, showing reluctant cooperation when thanked. After completing the mission, she negotiates the restoration of Scavenger's rank despite non-payment, retaining the Gekota communicators and developing a personal interest in the franchise. Her final appearance occurs in the Jailbreaker Arc, participating in the Second Reformatory's security trial. She instructs Yakumaru to covertly support Mikoto's team under the pretext of eventually stealing their objective, though the trial concludes before this plan unfolds. Throughout these events, Leader demonstrates strategic competence counterbalanced by intense anxiety facing Level 5 espers. Her character reveals complexities beneath an initially ruthless exterior through reluctant alliances and unexpected acts of assistance.