Every Little Detail

Sakura is trying to deal with her friend who has recently changed into a completely different person. She is confused when one day she mysteriously finds a letter in her room from a girl, Aya who says she lives in Australia. Sakura is confused about how she even got the letter as it appears in a box that her sister gave her before she died. Sakura and Aya cannot figure out how to communicate with each other other than leaving the letters where they find the other letters.
Aya is trying to find purpose In her life. She tries to look up Scarlet a J-pop band member, after Sakura mentions her in a letter. No matter how many searches she makes she can't find anything about Scarlet.
Sakura and Aya try to find a way to each other but eventually find out that while their worlds are similar they do not seem to be the same. Will they ever find a way to meet?