Frisk finishes a Genocide Route and gives their soul to Chara. Instead of taking their soul and using Frisk’s body for evil, Chara uses it to permanently hijack Frisk’s body and use it for good.
(Yes it’s another Genocide based AU, but that’s not the point)
It isn’t really an idea so much as a modifier or part of an idea, but I do have one thing planned for it
We could probably integrate it into the UnderSwap-esque suggestion, play off of Sans’s “Timelines jumping left and right, stopping and starting” quote and say its a result of Frisk’s Genocide.
Anyway, @DessEmberr , I think that your Underswap-esque AU idea was the one chosen (people who reject please comment your feelings) so I would like to ask if you would prefer to co-create it with me or leave the AU entirely in my hands