When exorcist are perform?

are they (priest) are putting the demon/devil into them. It seems that the person is more in hurt of recieving something within the body instead of something coming out. Just like when you take a dump, your relieved when the turd comes out, but could you imagine big jimbo standing behind you with a 28 inch stick and about to ram it slowly in your whowho. Ok. So with those 2 factors I say that priest who perform exorcisms is actually possessing the person to recieve a witchery spirit/demon/devil, could this be so?