Rei Hino is a teenage shrine maiden living and working at Tokyo's Hikawa Shrine alongside her grandfather. She is the reincarnated Princess of Mars, transforming into Sailor Mars, Guardian of Fire and Passion. Her civilian duties involve maintaining the shrine, performing exorcisms, and honing spiritual abilities through sacred fire rituals. Rei attends the elite private Catholic school, T.A. Girls' Academy, identifiable by its distinctive uniform. Innate psychic powers grant her precognition, a sixth sense, and pyromancy, enabling her to detect evil and glimpse futures via flame readings. These abilities caused others to perceive her as strange, leading to isolation before she joined the Sailor Guardians. Rei's personality differs across adaptations. The manga and *Sailor Moon Crystal* portray her as composed, traditional, and aloof, harboring deep resentment towards men stemming from her father's neglect during her mother's terminal illness; she disdains modern relationships and initially keeps emotional distance. The 1990s anime depicts her as hot-tempered, boy-crazy, and frequently arguing with Usagi Tsukino (Sailor Moon). All versions emphasize her fierce loyalty to the Sailor Guardians, especially Usagi, whom she protects relentlessly. Her relationship with Usagi evolves from friction to profound mutual respect, Rei often being the first to comfort or defend her. Her backstory reveals she is the daughter of politician Takashi Hino and the late Risa Hino. Blaming her father for his absence during her mother's illness, Rei moved to Hikawa Shrine. She befriended two crows, Phobos and Deimos (named after the moons of Mars), who serve as her familiars. Annually, Rei receives Casablanca lilies and a white dress from her father, though she later discovers his secretary, Kaido, selected them; Rei develops unrequited feelings for Kaido in the manga side story *Casablanca Memories*, reinforcing her distrust of men and romance. The 1990s anime shows her briefly dating Mamoru Chiba (Tuxedo Mask), creating a rivalry with Usagi, and interacting with Yuichiro Kumada, her grandfather's apprentice who harbors a crush on her. As Sailor Mars, her powers focus on fire manipulation and spiritual purification. Key attacks include Fire Soul (summoning engulfing flames), Fire Soul Bird (creating a fiery phoenix), Burning Mandala (generating a circular fire barrier), Mars Snake Fire (launching serpentine flames), and Mars Flame Sniper (using a fiery bow and arrow). She performs Akuryo Taisan in civilian or transformed states, chanting nine words while throwing *ofuda* scrolls to exorcise spirits. Transformation phrases like "Mars Power, Make Up!" evolve with new devices invoking "Star," "Planet," or "Crystal" power. Uniform upgrades reflect increasing strength: Super Sailor Mars features a heart-shaped brooch and translucent shoulder pads, while Eternal Sailor Mars adopts a layered skirt, knee-high boots, and star motifs. Character development is pivotal. In the manga's Dead Moon arc, Rei confronts an illusion mocking her chastity vow to Princess Serenity, reclaiming her Sailor Crystal and solidifying her disinterest in romance. The 1990s anime mutes this vow but emphasizes her growing loyalty to Usagi, particularly during battles like against Queen Metalia. The live-action series (*Pretty Guardian Sailor Moon*) shows her struggling with trust but accepting her role as secondary leader under Sailor Venus. Her cultural role as a shrine maiden blends Shinto practices with superhero elements. Rei's journey consistently highlights balancing spiritual dedication with combat leadership.