These are the tales of a certain housewife waiting for her husband to return home.... a man who started working part-time at a certain restaurant... and a certain high school student
visiting his friend who moved to the countryside...
I seriously don't know anything 
about that email or who Rie-san is.
.حقًّا لا أدري أيّ شيء عن البريد أو المدعوّة ريي-سان
Ich weiß nicht, was die Nachricht soll
oder wer Rie-san ist.
Eu não sei que mensagem é essa
nem quem é essa Sra. Rie.