- Name: Sekine Azusa (関根梓)
- Nickname: Sekkii (せっきー)
- Birthdate: June 14, 1996
- Birthplace: Nagano, Japan
- Blood Type: AB
- Height: 152.5 cm ("I shrunk..")
- Specialties: Dancing
- Dislikes: Running
- Favorite Food: Tuna, apples
- Least Favorite Food: Anything bitter
- Looks Up To: Niigaki Risa
- Hello! Project groups:
- Hello! Pro Egg (2004–2011)
- Up-Front groups:
-  Mano Erina - "Hajimete no Keiken" (はじめての経験) (as back dancer)
-  Mano Erina - "Haru no Arashi" (春の嵐) (as back dancer)
-  Mano Erina - "Seishun no Serenade" (青春のセレナーデ) (as back dancer)
- Eat's rice for breakfast.
- Has a habit of resting her chin in her hands.
- Her favorite spot is her chair at school.
- In January 2011 it was announced that Sekine Azusa would be part of a dance cover group called UFZS that represents Up Front and womens magazine Josei Jishin.
- On March 9, 2011 it was announced that Sekine Azusa had completed her Egg training.