According to the Catholic Church, are demonic unclean spirits the ghosts of dead humans, or the presence of fallen angels?

1 Samuel 28:7-8 ESV *The Medium of Endor Raises the Spirit of Samuel* > Then Saul said to his servants, “Seek out for me a woman who is a > medium, that I may go to her and inquire of her.” And his servants > said to him, “Behold, there is a medium at Endor.” > > So Saul disguised himself and put on other garments and went, he and > two men with him. And they came to the woman by night. And he said, > “**Divine for me by a spirit and bring up for me whomever I shall name > to you**.” Luke 24:36-39 ESV *Disciples Mistake Jesus for a Spirit* > As they were talking about these things, Jesus himself stood among > them, and said to them, “Peace to you!” But **they were startled and > frightened and thought they saw a spirit**. And he said to them, “Why > are you troubled, and why do doubts arise in your hearts? See my hands > and my feet, that it is I myself. Touch me, and see. For **a spirit does > not have flesh and bones as you see that I have**.” Matthew 12:43-45 ESV *Return of an Unclean Spirit* > “**When an unclean spirit has gone out of a person, it passes through > waterless places seeking rest, but finds none**. Then it says, ‘I will > return to my house from which I came.’ And when it comes, it finds the > house empty, swept, and put in order. Then it goes and brings with it > **seven other spirits more evil than itself**, and they enter and dwell > there, and the last state of that person is worse than the first. So > also will it be with this evil generation.” The unclean spirits, demons, seek to possess a body and therefore torment people for control of their bodies to hurt themselves and others. Jesus cleansed people's souls by casting out the unclean spirits called "demons". 1. Are angels spirits which possess immortal bodies? 2. Are humans spirits which possess mortal bodies? 3. Are demons the unclean spirits of dead humans (and Nephilim) that find no rest after death? 4. Do the spirits of the righteous dead remain at rest until they are resurrected? 5. **Are unclean spirits or demons the ghosts of dead people instead of fallen angels, which have spiritual bodies? Is this why the demons, which have no bodies, seek to possess one?**