Board Thread:Questions and Answers/@comment-28898329-20160901162911/@comment-26233737-20170101202316

I have some evidence. In Alphys's lab, there is a bag of, I think it was dog food? Anyways, if you haven't killed anything, the narrator notices the bag is half full, showing an optamistic viewpoint. If you have killed at least one monster, the narrator regards the bag as half empty, showing unoptamism. We all know that Chara supports killing, well, anything really. So it would seem weird that they would be unoptamistic if you killed something.

My guess is that the narrator is a third party, possibly Gaster, or Frisk, describing their observations to you.

I actually haven't seen much concrete evidence showing Chara as the narrator in the first place.