Despite the minor mistakes here and there, this is an otherwise well written and very interesting fic. I actually love the way you portrayed Frisk. As for the rest of the characters presented so far, they also seem pretty accurate for how you've written them. Excited to see what Frisk and her friends will do in this route!

Also: the only question I have so far about this whole thing is concerning the romance (as labelled in the genre). Sorry if I missed it but you didn't really say what the character pairing was...? (I'm pretty open to all ships in the Undertale fandom anyway, but just to be sure I'm guessing it's eventual Frisk/Sans, right?)

Keep up the great stuff! :)

ok so first, I commend you on a great story. I am eager to see how adult (slightly more verbal and less rash) Frisk will change the story we all know and love.

I made some notes on some errors I noticed, sorry for the error dump,
CH 2: The first date of the diary says 24XX and all the others say 23XX
CH 3: You wrote shoe instead of she at the end of the scene with the lamp
(when Sans is assuring Frisk that Pap isn't actually dangerous)
CH 4: when Frisk is asking about why Skeletons need air to talk the dialogue says "I aren't" (not sure if this counts as a 'tense issue' since the dialogue should be the same for both stories (sorry if it is :s) also the paragraph after that uses "you" instead of 3rd person

I'm not trying to be rude just helpful :) thank you again for sharing your awesome story and don't forget to never stop writing :D

awesome chapter

I knew it, Toriel babied her. That isn't bad, but now she's afraid to adventure on her own.

awesome chapter

This grown up Frisk is really dependant, but to be fair, Toriel must've babied her

awesome chapter

Aww we she stayed with toriel.. I like that you have changed the story instead or just rehashing it :)

What? Eleven years? ...looks legit :D

The diary format was nice on its own, because of the whole spelling errors on the beginning that got better as years went by.
This is definitely already different from the story, but I wonder how else it will be different.
Nice addition by including Frisk's reasoning for doing things - like why she wouldn't hurt Toriel, and showing a bit of hesitation after she got out.

I'm really enjoying the story so far!

I knew it, Toriel is the best mother in any video game so far. I should also mention that Frisk is freaking cute in this chapter. :3 She's cute in many stories, but more so in this one. She's almost like a baby, can barely talk, nice to everyone, that's just adorable :3

I just can't see accepting death like that, and then Flowey outright calls him Chara - implying he remembers the reset.

Though I'm excited to see if Chara and Frisk will interact more in this story.

Ooooh, I look forward to seeing where this goes. I like it. There are some walls of text here, but the writing's good to the point that it didn't matter. XD
Again, I look forward to seeing where this goes! Update soon!

awesome story