I would laugh at their ignorance.
nothing
Demons are what you call entities identified with Satan. The opposite would be Angels.
Satan's Hollow happened in 1982.
Satan is called shaytan.
Demons, if so desired by an individual can be called upon to take over their bodies. For this to happen a person would have to be totally evil and be willing to serve Satan, have him as their master and to be ready to accept the consequences of their actions. Remember, Satan does not reward for loyalty anything that is of worth.
Yes, people who worship Satan are called Satanist.
Satanists.
Satanism.
a pitchfork
A demoness ...
Satan would not be capable of love.