Popularly held belief says that demons operate in the places where deaths have occurred. It is also said that demons and other spirits operate in the places that is abandoned, especially old houses. However, I believe these are nothing but urban legends.
I don't think demons dwells anywhere sacred or clean. They are foul spirit and would always want to be where it is scary sort of for humans like the mortuary
Demons also operate in areas that have been defiled in one way or the other. Most religions kick against sexual immorality, as this gives easy access to demons.