Amana Ōsaki is a 17-year-old high school student from Toyama, born on December 25th, making her a Capricorn with blood type A. She stands 159 centimeters tall. Amana is the younger twin sister of Tenka Ōsaki, and the two are identical. Cheerful, outgoing, and fashion-conscious, she enjoys shopping, nail art, taking selfies, and following current trends. She refers to herself in the third person as “Amana” and possesses practical skills such as waking up early and being thrifty.

Amana is protective of her sister Tenka, who faces self-esteem issues and fatigue, and she often takes care of her through daily acts like brushing her hair, helping with morning routines, or even pushing her in a baby carriage during outings. She initially suggested they become idols, partly to showcase Tenka’s appealing qualities and partly as an enjoyable activity they could share. As a member of the unit ALSTROEMERIA alongside Tenka and Chiyuki Kuwayama, Amana naturally assumes the role of leader and conversation starter, ensuring that both of her teammates have a chance to contribute. Her original motivation emphasized experiencing fun and creating memories unique to the present moment, but participating in idol activities like the Wonder Idol Nova Grand Prix shifted her perspective toward recognizing the importance of teamwork and collective purpose.

Despite her bright and friendly demeanor, Amana harbors a fear of change and a deep wish for her happy circumstances to remain unchanged forever. This is most evident in her relationship with her sister: while she is devoted and caring, she also fears separation and relies on the stability their bond provides. Her journey as an idol involves learning to balance personal enjoyment with shared ambition, confronting her insecurities about the future, and trusting in the strength of her bonds even as circumstances evolve.