Rena had dedicated her whole life to becoming an idol. However as a child, she was a terrible singer and could barely sing a single note on key. Rena often holds a somewhat serious demeanor and can sometimes be hard on herself and others, but she is nevertheless someone who puts her all into everything she does. It is later revealed that she is the biological younger sister of the deceased legendary idol Akari Amasawa. She doesn't like having fame in the shadow of her deceased sister.