question but how would chara and asriel react if it was an older frish that fell instead of the kid that's there now like a grown version of themselves how would they react and what would a grown version of frisk look like ?
An older version of Frisk would look pretty similar, just taller and better dressed. Chara would still try to kill them using the same tactics as in the comic. Send them into the death traps, and when that doesn’t work, use the knife. However, Chara would have to be much more careful; an adult is stronger than a child!
As for Asriel, it’s hard to say. Frisk wouldn’t have the cute kid thing going for them anymore, so maybe Chara would be able to convince Asriel to let them kill Frisk before they got to town.