Well, if angels aren't real neither are demons. But science studies the creation as we know it, not as God knows it. So science has nothing to say either way.

As a bishop, I was responsible for overseeing the ministry of exorcism. (I am now retired, so don't ask me for one...) Exorcists are people with a rare gift, called "discernment of spirits" in the Bible, and who also need to be trained. No one should ever attempt an exorcism on his or her own. You are right about the damage that can be done.

Furthermore, we tend to be more fascinated with demons, Satan, hell, than with God. If anything, that is a temptation—heaven is full of joy and love, hell is BORING. And as C. S. Lewis pointed out in The Great Divorce, the gates of hell are locked from the inside.

So let's focus on cultivating love, joy, peace, patience, kindness, gentleness, and self-control.