Naho got into a fight with Kakeru on New Year's Eve, and never managed to apologize to him before he passed away. At least, that's what the letter from the future says. However, Naho now believes that she's capable of dealing with whatever may come up, and faces New Year's Eve head-on.
The world our ten-years-older 
selves sent us letters from
...العالم الذي أرسلت أنفسنا بعد عشرة سنوات الرسائل لنا
Die Welt, in der wir in 10 Jahren
die Briefe verschicken,
El mundo en el que escribimos
las cartas dentro de diez años
El mundo en el que escribimos
las cartas dentro de diez años
Le monde d’où proviennent 
les lettres
Il mondo in cui abbiamo ventisei anni
e mandiamo lettere a noi nel passato
O mundo no qual a nossa versão
 que enviou as cartas vive...
Мир, из которого
будущие мы отправили письма,