i tried dropping the ball of junk item and stumbled across some interesting dialogue.
it gives you a yes or no prompt. this is what it says if you pick no:
this is what it says if you pick yes:
if it was a ball of junk then why does kris feel so bitter about it being thrown away?
okay… potential theory?
if you accept that chara is the narrator of undertale, then, perhaps kris is the narrator of deltarune? In deltarune, you have to erase kris’s save the first time you save your game, and at the end, when kris rips the soul out, the player has control of it in the bird cage and can move it, implying that kris is seperate from the player and we ARE controlling them like a puppet. Perhaps the ball of junk is, in fact, something completely different, and kris, the narrator, is lying and saying it is a ball of junk when its like, i dunno, a locket, or something else actually breakable, to try to stop the player controlling them from throwing it away or doing something to it?
I saw a post talking about how you can move the SOUL around in the final scene of deltarune, once it’s been thrown into the bird cage. I can confirm this is true.