How would you feel if kiri turned into a villian in the later movies?

I was just thinking about the most iconic characters and that the most interesting ones are the people who start out as heros and end up villians like eren from attack on titian. Anakin from star wars. Paul from Dune.

I know kiri is a very imporant character but what if when they go to earth in the 4th movie. Something happens and she changes?