They had 3 weeks.  And only until the last day did Chanyeol finally replace 'sorry' with 'i love you'

Once upon a time, there was a mysterious oak tree which has 2 other trees growing under it. A diary lay open between the both of them, the page seemed to stop at day 1000th and a letter was beside it, it was still sealed and the recipient of the letter never got the chance to open it. There was no more need to either.     "Promise."