Rei Hino (火野レイ), Sailor Mars, is a 14 year-old girl who attends T*A Private Girls' School. She is an Aries, and her blood type is AB. This strong-willed soldier works as a miko (or a shrine maiden) at Hikawa Shrine, where she lives with her grandfather. Her dream is to one day become an idol and a wife.

Rei is passionate, spiritual, and determined young woman. Behind her temper lies a great sense of loyalty and compassion for those she loves-- especially with Usagi. In the anime, the two are constantly bickering, which Naoko attributes to the fact that they are such good friends. In the manga and live-action series, Rei seems especially close to Minako.

Rei's love life is somewhat inconsistent throughout the different versions of Sailor Moon. In the very beginning of the anime, Rei briefly dates Mamoru. She met him while she was with Usagi, and the two bonded over making fun of the little odango atama. Their "relationship" consisted of Rei's child-like crush on Mamoru, who seems overwhelmed by her attachment and a little uninterested. Their relationship quickly ends when Usagi and Mamoru's true identities as Serenity and Endymion are revealed, however, sporadic moments throughout the anime which suggest that Rei is still attracted to Mamoru. In the manga and live-action series Rei wants nothing to do with personal romantic relationships, while there doesn't seem to be any comments about her love life in the musicals. Throughout all versions of Sailor Moon, Mar's mission as a soldier seems to take priority over romantic love.

Mars Trivia
 Rei's name in the English dub of the anime is "Raye Hino"
 The name "Rei" has is pronounced the same as a Japanese kanji character meaning "spirit" (霊).
 After middle school, Rei is the only one out of the five inner senshi who does not attend Juuban Municipal High School.
 In the anime, Rei first appears in Episode 10 - "Cursed Buses! Fire Senshi Mars Appears"
 In the manga, she first appears in Act 3 - "Sailor Mars"
 In the live-action, she first appears in Act 3 - "The Third Senshi is Miko Rei"
 April 17 is Rei's birthday.

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Mars definitely needs some more love.  

I love her characterization, personality (can be very amusing at times) and devotion to her friends and mission as a Sailor Senshi. She's my second favorite main character after Neptune. <3

Reiiiiii. My one true love. <3

I confess, in my childhood I hated her, because she was very warmed, intense and and fought a lot of stupid reasons! @@

when I read the manga I saw, she is different! She is cool... And now she is one of my favorites senshi

fave:

Rei has always been one of my most favorite Senshi!

Rei/Mars is fiery, known for temperament and just doesn't take crap from anyone. I like her long raven hair and to me, she's more beautiful than Minako/Venus, the "senshi of love and beauty" supposedly represents more popular beauty standards. In a fan fic I recall reading, the writer posted her birthday April 7th (the middle of the sign Aries) and her birthplace Phoenix AZ, in case the senshi have such info. although not in the official SM universe biography. Fan fics are more fun when writers come up with their own versions of the senshi's lives and personalities. I can see Rei is from a desert climate, her representative Mars is a dry dusty planet and she wears a Phoenix/firebird medallion given to her as a child (it's somewhere in the SM anthology). Not surprisingly, she would be in Japan to become a Shinto priestess, even if she's from the US based on what I read on that fan fic.

I think Rei is kind of cool, even if her temper can be a bit off putting. In the manga she is twice cooler, I sometimes became Rei when I played Sailor Moon with my cousin during my childhood.

Spare me the hate, but I HATED her in the original 90s anime.  She needlessly bickered with Usagi, and clung to Mamoru like there was no tomorrow EVEN THOUGH he SHOWED ABSOLUTELY no interest in her at all.  However, I actually love her in Crystal and in the manga, she's not as "prissy" or always bickering with Usagi, and so elegant!  Love her in Crystal.

Rei is a very amazing girl and she's my favorite character in the entire Sailor Moon series, plus I can also relate to her too.

She's so cool (and fiery, from different perspective )!

Oh wow this just brought me back to this old Sailor Mars AMV. It's really good, for the time period at least. xD

My favorite version of Sailor Mars is in the manga. I don't know but I just love her portrayal in this version (the original version) I love how she is cool headed and calm and her poise and elegance in this version of her is just admirable. I'm not actually a big fan of her anime counter-part and she was initially my least favorite  senshi at first (though the original Japanese language version of Rei is so much better than her american dub counter-part). I also like that she is a beautiful girl that people are wowed by when they see her in the manga, they did not really play up the beauty aspect of her characterization in the anime and I thought that was a shame. She actually mildly reminds me of Kikyou from Inuyahsa since they are both mikos and have spiritual powers. Her backstory with her father and her father's assistant always made sympathize with her. It's only a shame that she developed such a strong distrust of men because of this. I thought that was sad.