Ano Ko ni 1000% (1989)

That Girl is 1000%

Cheerful Azusa Kawahara serves as the manager of her high school soccer team, which includes Morisaki Ikumi, her childhood friend and mutual romantic interest. Given their close relationship, Azusa inevitably takes notice when Ikumi's schedule becomes unusually busy. Azusa is taken aback when she secretly witnesses Ikumi outside of school in the company of an unfamiliar female student. Suspicious of this interaction, Azusa begins to wonder whether her feelings for Ikumi are actually mutual. [Written by MAL Rewrite]