A series of letters written between Kai and friends, with each letter revealing a little something between each friendship.  ForewordThis was meant to be 2 part series, but I feel like itll be a mini-series of letters. Part 1 - Why?: DO writes a letter to Kai to reveal how he has felt and how he still feels.Part 2 - My Dear: Kai reads the letter from DO and answers what really happened.Part 3 - Remember?: Taemin writes a letter to Kai (after being suggested by DO) and unlike DO and Kai, he actually keeps his cool.