Jun the Swan, designated G-3, is the electronics and demolitions expert for her team. Orphaned young, her parentage is Japanese/American in the original series but Japanese/English in the OVA. Her parents died due to war (original) or nuclear terrorism (OVA). She lived at the Shirayuki Orphanage, where she discovered toddler Jinpei in the Jupiter Mountains and raised him as her adoptive brother. Both came under Dr. Nambu's guardianship around her thirteenth birthday. The OVA adds traumatic experiences led her to join a motorcycle gang for protection in her early teens, contributing to a more withdrawn personality. Civilians know her as the manager of Snack J café, serving as the team's gathering spot and her residence with Jinpei. She enjoys motorcycle riding and pilots the transformable G-3 vehicle. This mecha functions as a high-performance motorcycle, reconfiguring into a hover-cycle for land, water, or short-distance air travel, achieving 700 km/h on land and 200 km/h on water. Post-episode 68, it gained twin rocket launchers. The 1994 OVA reimagined G-3 as a futuristic Harley Davidson transforming via a G-Bracelet into a monowheeled hovercycle. Physically, Jun stands 160 cm tall with green eyes. Her original design features dark green, shoulder-length hair curling at the ends; the OVA redesign gives her shorter brown hair and a more developed physique. Her civilian attire typically includes a red-and-navy or pink "3"-emblazoned T-shirt with striped bell-bottoms or capri pants. Her Bird Style uniform is a pink sleeveless mini-dress, white elbow-length gloves, knee-high go-go boots, a white cape lined with red, and a swan-inspired helmet with an orange visor. The OVA version modifies this into a pink-and-white split-skirt dress. Personality-wise, Jun exhibits bravery, independence, and strong responsibility during missions, maintaining calm under pressure while utilizing expertise in explosives, karate, and aikido. She possesses a notable motherly instinct toward Jinpei, though their sibling relationship includes frequent arguments. She harbors unreciprocated romantic feelings for team leader Ken Washio; his dedication to their mission creates tension. Her interactions with teammate Joe Asakura involve professional respect, particularly when he challenges her emotional hesitation during a critical mission involving her childhood friend Koji—a Galactor agent she ultimately neutralizes using a Bird Missile. Her primary weapon is a customized yo-yo with a concealed blade, used for combat and remote detonation, reflecting her sabotage role. Character development shows increased assertiveness, especially confronting Ken about his self-destructive commitment and emphasizing duty over mutual feelings. The OVA iteration explores her emotional resilience, depicting reluctance toward romance due to past trauma.