Akari Amasawa, a legendary idol, won the first nationwide Selection Project idol audition. Her singing career started young, showcasing natural vocal talent and a charismatic stage presence that captivated audiences. She became a beacon of hope for aspiring idols, profoundly inspiring individuals like Suzune Miyama. Hospitalized with a chronic heart condition, Suzune found emotional strength and encouragement through Akari's songs.

Tragically, Akari died at age 18 in a traffic accident. Prior to her death, she had registered as an organ donor, specifically wishing to donate her heart. Consequently, her heart was transplanted into Suzune, fulfilling Akari's desire to bring hope beyond her passing. Her death occurred three years before the seventh Selection Project's main events.

Akari's legacy deeply shapes the narrative. Her younger sister, Rena Hananoi (born Rena Amasawa), adopted their maternal surname to forge her own identity distinct from Akari's fame. Rena enters the seventh Selection Project aiming for recognition based solely on her own talents. Akari's musical influence also endures within the audition; contestants perform her song "Only one yell" during regional finals.

Physically, Akari had black hair, petrol-colored eyes, and stood 167 cm tall. Her name (天沢 灯) incorporates the kanji for "heaven/sky" (天) and "marsh" (沢) in her surname, while her given name (灯) means "lamp" or "light," reflecting her inspirational role. She declared, "Singing is my life," underscoring her dedication. She released several singles, though specific titles and discography details remain partially unconfirmed.

Her influence extends broadly; she persists as a cultural icon within the series' universe, recognized as a foundational figure in the idol industry whose impact continues through those she inspired.