Book 1: Based on Krystal's Single "All of a Sudden", the story revolves around the suppressed feelings of two people who've been together for a long time.

What would a confession all of a sudden do to their relationship?
would it be a happily ever after?

Book 2: 

L's P.O.V after leaving Krystal behind. Will they be able to find love the second time around?

(Lyrics are taken from L's single This Song is for You)