Name: Seiya Kou Gender: Male (Before transformation) - Female (After transformation) - In a way, the gender can be considered unknown. Age: 16 Blood Type: A Favorite Subject: Physical Education Least Favorite Subject: Classics Favorite Food: Hamburgers Hobby: American Football Club Activity: American Football Club Symbolic Color: Sky Blue Favorite Saying: Integrity (清廉潔白) Active as a member of the idol group Three Lights. Seiya is the leader and main vocalist of Three Lights. Characterized by long hair tied in a single ponytail. The guardian star is not mentioned. Transforms into Sailor Star Fighter, a member of the Sailor Starlights. Transformation Item: Sailor Change Star. A star-shaped pendant with wings. Sailor Star Yell: Resembles the Sailor Change Star. Used to perform special attacks. Maintains a relationship that is nothing more than classmates who know each other's names but aren't particularly close. Normally a man. Female only when transforming into a Sailor Guardian! Important. Ordinary people do not know they are Guardians.

Birthday: May 30 (Gemini) Gender: Male (Before transformation) ↔ Female (After transformation) - In a way, the gender is unknown. Age: 16 Blood Type: AB Favorite Subject: Classics Least Favorite Subject: None Favorite Food: Sushi Hobbies: Poetry recitation, Computers Club Activity: Literature Club (Old series) / Gardening Club (Sailor Moon Cosmos) Favorite Saying: Life is a drama, everyone is the same (人生はドラマ、人はみな同じ) Symbolic Color: Purple Active as a member of the idol group Three Lights. Responsible for songwriting, composition, and keyboards within the group. The guardian star is not mentioned. Transforms into Sailor Star Maker, a member of the Sailor Starlights. Sailor Change Star: A star-shaped pendant with wings. Thoroughly realistic and conservative, Taiki dislikes bothersome things. Possesses an intellectual and cool image, which matches the actual personality. Can be quite blunt, coldly denying things like romance or dreams. Exceptionally, when Taiki bursts into laughter, even Seiya and Yaten remark, "How long has it been since you last laughed?" Normally a man. Female only when transforming into a Sailor Guardian! Important. Ordinary people do not know they are Guardians.

Birthday: February 8 (Aquarius) Gender: Male (Before transformation) ↔ Female (After transformation) - In a way, the gender is unknown. Age: 16 Blood Type: B Favorite Subject: Art Least Favorite Subject: Physical Education Favorite Food: Caviar Hobby: Photography Dislikes: Effort Club Activity: None Favorite Saying: Hundred Flowers Blooming (百花繚乱) Symbolic Color: Light Green The guardian star is not mentioned. Transforms into Sailor Star Healer, a member of the Sailor Starlights. Acts as the mood maker for the group, providing the most fan service and smiling gently. However, in reality, Yaten is moody and narcissistic. Never makes childish judgments. Among the three, Yaten dislikes Earthlings—especially women—the most, to the point of throwing away love letters without reading them. Normally a man. Female only when transforming into a Sailor Guardian! Important. Ordinary people do not know they are Guardians.