On the anime Yu Yu Hakusho, it was implied that Raizen slowly killed himself by refusing to eat humans. Do all demons need to eat people to survive? It was implied when Mukuro found the concept scuicidal that it is clear that Raizen's people weren't the only ones who need to.
Another point that confuses me is if they all do, then that probably means that Yukina probably does occasionally, seeing as to how she seems relatively healthy. Part of me just can't see her doing that, having the close friends that she does that are humans.
Anyone else have something to say on that subject?