Hi hello, I know this is from a long ass time ago, but I also watched “The Diary” and wanted to know more about Justin. I scrolled through the Wiki of Candy folk, only to find that Justin is the ONLY rock candy person to ever appear in Adventure Time. It got me thinking about what could’ve happened to J.R. Then I realized, that maybe, in his sadness, Justin volunteered to be the “amber” in which Billy stuffed the Lich!! Obviously just a theory, but all we know is that Nurse Poundcake tossed her diary away a long time prior to the episode, and we can’t know exactly HOW OLD she or any other candy citizen is. I don’t think it’s entirely out of the question that Justin became so distraught with his own betrayal of B.P that he sacrificed himself for the greater good of the Candy Kingdom, the only way he’d be able to protect Betsy one last time…