The letter from the future details the regret felt by everyone for being unable to celebrate Kakeru's birthday. As such, high school Naho and the gang pester Kakeru about what he wants until the big day. On the other hand, 26 year-old Naho and the gang gather at the late Kakeru's grandmother's house to celebrate his birthday, like they had promised in the past.
Because I broke my promise to my mom.
.لأنّي لم أفي بوعدي مع أمّي
Weil ich das Versprechen
mit meiner Mutter gebrochen habe.
Porque no mantuve mi promesa.
Porque no mantuve mi promesa.
Je n’ai pas tenu 
la promesse faite à ma mère.
Ho infranto la promessa 
che avevo fatto a mia madre.
Eu quebrei a promessa 
que fiz à minha mãe.
Потому что пообещал маме и не пришёл.