Wakamiya, Shiki

She was one of the Japanese representatives in the women's soccer in middle school and was chosen to join the American league. She is shown to give Sora advice and motivation when he was contemplating on not continuing soccer.

[Spoiler] She is actually Tsuyoshi, Sora's childhood friend who moved away due to her parents' divorce, and who was mistaken as a boy due to her boyish nature then. Due to her weak physical status, she admired Sora greatly for his skills in soccer and strived to be like him.

Later, the news announce that Wakamiya Shiki is actually dead, and she only showed herself to Sora as a wish to see him play soccer happily once more. [/Spoiler]