Leorio Paradinight is a tall, muscular young man standing 193 cm tall and weighing 85 kg. Despite being a teenager at the series' start, his mature appearance leads characters like Killua to mistake him for an older man. He sports black hair in a spiked crew cut, small brown eyes, and typically wears a dark blue business suit with tea-shade sunglasses. Motivated by the loss of a childhood friend to a curable illness that was financially out of reach, Leorio aims to become a doctor providing free healthcare for the poor. He seeks a Hunter license to fund his medical education and charitable work, often masking this altruism with claims of desiring wealth. As applicant #403 in the 287th Hunter Exam, Leorio befriends Gon, Kurapika, and Killua. He demonstrates medical knowledge during the navigator test and physical endurance in the marathon phase. However, he struggles in combat, exemplified by an impulsive, unsuccessful attack on Hisoka that leaves him temporarily incapacitated. His loyalty emerges early, such as when he insists on confronting dangers alone to protect Gon and Kurapika during the fourth phase. After passing the exam, Leorio aids Gon in infiltrating the Zoldyck Estate to rescue Killua, showcasing physical strength by opening the Testing Gate and unwavering friendship. In the Yorknew City arc, he supports Kurapika against the Phantom Troupe, helping capture Chrollo to save Gon and Killua. His medical skills prove critical treating Kurapika after overusing "Emperor Time." Absent during the Greed Island and Chimera Ant arcs, Leorio reappears when Gon is critically injured. He interrupts the Hunter Association Chairman election to publicly condemn Ging for neglecting Gon, striking him with his newfound Emission-type Nen ability, "Warp Punch." This act of protectiveness garners significant Hunter support, though he withdraws from the election after Gon's recovery. Leorio later joins the Zodiacs as the "Boar," replacing Ging. Working under Cheadle Yorkshire, he focuses on medical training for the Dark Continent expedition and serves in the Black Whale's medical facility during the voyage. His confirmed Emission-type Nen abilities include "Ultrasound" for diagnostics and "Warp Punch" for combat. Personality-wise, Leorio balances brashness with deep compassion. He is quick-tempered and provides comic relief through loud outbursts and impulsiveness, like dangling an opponent off Trick Tower. Melody describes his heartbeat as "the nicest in the city," emphasizing his underlying kindness. He consistently prioritizes friends' well-being, whether attempting to contact the isolated Kurapika or advocating for Gon's life during the election.