User blog comment:Miskos3/Fairy Tail Chapters 532 & 533, Review/@comment-7070784-20170422053208/@comment-5303512-20170424020854

Yes, Lucy believed that there was a secret and knew that there was a code in the book because of there was a spell that prevented anyone but Coby from reading it. I mean, she knew the moment she finished reading it it was for Coby and that it was all the letters to him despite it still being Day break. That by definition was deciphering a code which none of the text in the book as Day Break was normal.

And no, Coby never opened the book when the spell was broken, so no, I don't admit?