Triumph over self
Rin's chest swells with pride, her empty eyes are condescendingly looking down upon the living as her half-open mouth smirks at their pettiness. She seems to be enjoying being dead to the fullest, but of course under the smug façade there is no Rin to begin with. While Rin's death is the whole source of her self-indulgence, it also ensures there is no such a self to indulge. Rin killed herself looking forward to all sorts of post-mortem joy: the majesty of standing tall on the pedestal, the reveling of trampling her own head, and above all the swagger of trifling life - and just as she expected she got absolutely nothing. No regret of not getting anything and not even satisfaction of such expectations being right. It was because Rin knew there would be no conclusion either way that she could simply enjoy the anticipation itself. Rin eagerly awaited for things that would only come after her death with every fiber of her being, as she knew this being won't be there to get disappointed. This was Rin's triumph over her own self. And it was not getting to be there for her greatest triumph that made this triumph so truly great.