Setsuna realizes that Haruki has been staying at Kazusa's house this whole time, and she reveals her true self to him: cowardly, introverted, and pathetic.  But Haruki accepts her as she is.  The boundary between them is broken, and the bonds between the three grow stronger as the school fair draws near.  But Kazusa is skipping sleep and food to work on her "last trick" before the school concert.
And for complaining when 
you're doing your best
Und dass ich mich beschwert habe,
obwohl du dein Bestes ...
Y por quejarme cuando te esfuerzas
Siento haberme quejado cuando te estás
et de te faire des reproches,
E por reclamar quando você
está fazendo o máximo possível