Kuroha's younger sisters abruptly visit Sueharu's house to tell him that she has developed amnesia. All her memories from summer break onward are gone, and they stop right when she was about to confess to Sueharu. So she suggests starting over from the moment of her own confession and erasing everything she did during the cultural festival. But Kuroha's behavior is making Shirokusa suspicious...
That's one part of it, but not all.
.هذا جزء منه، لكن ليس كلّه
Das ist einer der Aspekte, aber nicht alles.
Es una de las ideas, pero no lo es todo.
Es una de las ideas, pero no lo es todo.
Ce sera une de nos activités,
mais il n’y a pas que ça.
Questa è solo una parte. C'è dell'altro.
Será uma das faces, mas não é apenas isso.
Это лишь часть задумки... 
Есть ещё кое-что.