Considering Toby is hack...
Susy is the most likely the main character of Deltarune, she's the "not the chosen one, but the hero who saves the day anyway" cliche.
I bet that the normal route will end with some slop happy end where Susie chokeslams the prophecy into the ground and there's only so much Mary Sue wank I can take.
Do you guys think we'll be able to kill her on snowgrave or not?

This is the most faithful depiction of those 2 I've ever seen