| Kou Seiya |
|Aliases:||Sailor Star Fighter|
Tokyo, Japan (briefly)
Idol (briefly), student (briefly)
|Birthdate:||July 30th (♌)|
|Gender:||Female (Disguises as male)|
|Likes:||The color red, ruby, hamburger, physical education, American football, Usagi Tsukino|
|Anime:||A Goodbye and an Encounter! The Destiny of Flowing Stars|
|Anime Voiced By:|| Shiho Niiyama (Japanese)|
Melissa Hutchison (English)
Kou Seiya is one of the members of the Three Lights idol group, and is the civilian identity of Sailor Star Fighter. She is a student at Juuban Municipal High School, and the lead singer of the Three Lights.
Seiya has blue eyes and long, hip-length raven hair that he keeps tied in a low ponytail. As the leading vocalist of the Three Lights, Seiya is commonly seen wearing a red formal suit jacket with a navy blue long sleeved button-up shirt underneath with a yellow long tie at the collar, red formal pants and black shoes. Seiya also wears a pair of silver moon earrings on both of his ears. He sometimes handling the red rose during concerts or as a weapon when he threw the rose on Sailor Tin Nyanko to rescue Usagi as Eternal Sailor Moon from getting her star seed.
When he studies at Azabu Juuban High School, he wore a different school uniform like both Taiki and Yaten to differ the other male students wearing a standard male school uniforms.
He also wears various casual outfits when he hangs out with Usagi while he retains wearing his silver moon earrings. With the exception of his athletic attire where he is not wearing his silver moon earrings.
As Sailor Star Fighter, her height falls in the middle of the other Starlights and like the other Starlights her male civilian identity is changed to their respective female identities during their transformation.
Her sailor fuku, identical to the other Starlights, is a black two piece outfit, consisting of a bikini-like top and hotpants. She wears knee-length boots and elbow-length gloves. She wears a golden beaded tiara, beaded belts on her waist and golden star earrings. Her secondary colour is light blue. She also wears a light blue belt-like choker and belt-like straps on her upper arm.
Seiya's personality was considerably lighter than that of the other two Starlights. He was much more childlike in his attitude, with a slightl prankster edge to his character, and there were brief moments when he was not thinking about his mission. He had a cheerful disposition and was much more easygoing. He was also more willing to become close to Usagi and her friends, while the other two Starlights mainly kept to themselves and originally refused to work with the Solar System Senshi at all. As mentioned by Taiki and Yaten, Seiya is also a sore loser.
Seiya is first seen walking past Mamoru and Usagi, who are on their way to the airport. His attention is caught by Usagi, but then he walks away. He later sees Usagi in a shooting location and recognizes her when she was trying to get a good look at what's happening. He first appears in Episode 173 when he meets Usagi while Taiki Kou is having a shoot with an actress which Usagi did not recognize him for seeing her in the airport. When the Taiki's partner and actress turns into a Phage by Sailor Iron Mouse, the trio transforms into their Sailor Starlights form in off-screen and she was the one who snaps her fingers when Eternal Sailor Moon fights off the Phage. They wanted to eliminate the Phage but Eternal Sailor Moon tells them not to stating that the Phage and the actress is the same person which it glows the Crescent Moon on her forehead. She manages to heal the Phage with Starlight Honeymoon Therapy Kiss. The Sailor Starlights notice her actions and acts as anti-heroines towards her.
As time passes where he develops her feelings for Usagi and her identity as Sailor Moon, Seiya becomes overprotected to Usagi even being kick out by both Taiki and Yaten for his actions. When Sailor Tin Nyanko targets Usagi for her star seed, Seiya along with Rei, Makoto, Minako and Ami are searching for her. By the time Eternal Sailor Moon defends herself from being attacked, Seiya saves her by throwing a red rose and injures Sailor Tin Nyanko which she recognizes what Mamoru did as Tuxedo Mask. Seiya angrily tells her if she tries to attack her, he will stand and fight as he transforms into Sailor Star Fighter and unleashes her Star Serious Laser at Sailor Tin Nyanko, allowing Eternal Sailor Moon to hit her with her Silver Moon Power Kiss which it nearly hits her. After the incident when it rains, Usagi reveals that Mamoru wasn't receive any calls and message which she does not know that her boyfriend was killed by Sailor Galaxia from the very beginning as well as the red rose that he threw earlier. Seiya comforts her and asks. "Am I not good enough?". With that he decides to find Mamoru for Usagi's sake.
After Princess Kakyuu was killed, she teamed up with her fellow Sailor Guardians and attacked Galaxia and stood beside Eternal Sailor Moon to protect her and during their last defense the trio protects Eternal Sailor Moon when Galaxia planned to get her star seed only to be witnessed Eternal Sailor Moon attempts to heal Galaxia with her Silver Crystal which shows her Star Seed and was forcibly taken by Galaxia and Eternal Sailor Moon was forcibly reverted back into Usagi with Pink Ribbons are hanging loose on her naked body.
The Sailor Starlights watch their confrontation between Princess Serenity and Galaxia in the remainder of the final episode and after Galaxia was healed, Sailor Star Fighter returned with the other Starlights see Kakyuu was back to life along with the Inner and Outer Sailor Guardians and watching Chibi Chibi leave and stating the Light of Hope was in everyone's mind. After the incident, Seiya finally say goodbye to Usagi after she finally found her boyfriend back and he also tells Mamoru to protect her before he transforms into Sailor Star Fighter and she with Sailor Star Healer, Sailor Star Maker and Kakyuu to leave Earth restore their homeworld. The Starlights were last seen by Haruka, Michiru, Setsuna and Hotaru.
- Like the other Starlights, her given name in male disguise is "Kou" but is usually referred to by surname to differentiate between the three.
- In the first anime series, Seiya has one image song: The One-Sided Love as Far Apart as the Galaxy.
- His hairstyle and appearance is a mixture of Mamoru Chiba and Haruka Tenou.
- He is seen blushing the most of the Three Lights.
- In the Materials Collection, Star Fighter Kick, Star Fighter Punch, Star Fighter Uppercut and Star Fighter Attack were additional attacks listed for Sailor Star Fighter, which were never used in any versions and was never specified what they did.