As I understand it, they don’t “go” anywhere. They simply leave the body, they are cast out. They then will often go into someone else. Demons will not leave Earth until Judgement Day.
If anyone does not believe in possession, I recommend they listen to the exorcism recordings of Anneliese Michel, the case that inspired most of the exorcism movies. Truly spine-chilling.
yes that is what I would think as well