Koyama Seina (小山星流) is a member of Up Up Girls (Kakko Kari). She joined the group on December 17, 2020 as a new member alongside Furuya Yurika, Suzuki Meina, Kudo Sumire, Suzuki Ayu, Aoyagi Yume, and Sumida Haruka.
Koyama Seina was born on June 2, 2001 in Tokyo, Japan.
- Name: Koyama Seina (小山星流)
- Nickname: Seina (セイナ), Sei-chan (せいちゃん)
- Birthdate: June 2, 2001
- Birthplace: Tokyo, Japan
- Blood type: O
- Western Zodiac: Gemini
- Eastern Zodiac: Snake
- Height: 154.5cm
- Shoe Size: 23.5cm
- Up Up Girls (Kakko Kari) Color: Orange
- UP-FRONT GROUP Status:
- 2020-12-17: Joined UP-FRONT CREATE (in partnership with YU-M Entertainment)
- UP-FRONT CREATE Groups:
- Up Up Girls (Kakko Kari) (2020-present)
Discography Featured In
- Up Up Girls (Kakko Kari)
- During the Up Up Girls (Kakko Kari) audition, she was known as Seina (セイナ) and her number was 18.