No ritual anywhere will help OP with himself, he sees the "demon" as separate. The third eye does not work the way you have imagined it, for if the "demon" entered there it would not be a demon. The lower vibrating astral energies would enter through the solar plexus and that is rare. These demons that the bible thumpers are scaring people with are their own inner demons that they have shifted to the unconscious. No demon anywhere can attack you if at some level you have not given your permission. See the demon as fear, for that's what it is, then sit fearlessly through the experience. Then do not be afraid of it or judge it, simple breathe in light and eventually you will rid yourself of this fear that you have carried so long.

The times that we are in now are designed to bring up all fears, so many buttons will continue to be pushed, you will either bend and merge with the wind of change now sweeping your world or you will crack and die in fear. Many christians will begin to go insane, this is a good sign because they will finally be getting an accurate picture of themselves so that they can change it if they are courageous enough. Time will tell......