Why Bother? (Sans x Chara)
Frisk resets, but gets a little help from Error!Sans to hack into Chara's files and delete all the routes she made Frisk do, and takes away Chara's fight button. No one remembers anything, not even Sans. And even better, Chara gets her own body and starts with Frisk from the beginning, and all the way to the end, of a pacifist route. Chara and Frisk are both female, and Frisk is 14, while Chara is 16.