Haruki hears about Kazusa's moving from her mother, who she hadn't been on good terms with.  He feels betrayed and angrily confronts her.  But his words force open the door to Kazusa's heart, which she had desperately tried to keep closed so that the three of them could stay together.
Oh, and your student discount card application.
Oh, und für deine Schüler-Rabattkarte.
Ah, y la tarjeta de descuento estudiantil.
Ah, y la tarjeta para los 
descuentos de estudiantes.
Ah, e sua carteira de 
estudante para descontos.