If you watch closely u will see there is acutely Two different things. My reasoning: At first the “thing” Could only get into the house. One from the stairs and the other from the roof;Then during the activity in the room one was trying to get the girl, and the other was trying to posses the girl; And then more proof was when they did the board thing, not only did it prove its a ghost but that it was strong enough to incarnate fire. If this was a “alien” or something it would not have done that. To be honest if this was real it would be more like this. Angels (roof dude) Vs demon (possessor and one coming from stairs) Fighting over her soul, or just trying to get her. Or Alien (the feet) vs Ghost (umm…ghost lol) Trying to get her. Here is my reasons for th AvD. We have no idea what angels look like, they could have weird feet like that lol, and then the demon because of the board thing and the possessing. AvG; The foot thing can prove it was an alien not a ghost, and the shadow thing, if u look into a camouflage that can give invisibility is by Bending light around the body. This will give the wearer invis, and no one can see them, BUT! just because the light is bent around them doesn’t mean it will not cast a shadow that is able to be picked up by the camera. Now for the ghost, the board thing kinda give it that, and the possessing thing and the fact it didn’t always cast a shadow. When she was possessed both times, no physical action was recorded, but when a shadow was casted there was. Showing there was not one but 2 or more beings after her. ..>< More to add to Demon/Ghost. The Photo, Demon’s are said to feed on fear and all that stuff, they would have planted that to strike fear into her and gain more power. >>>><<<<<<!!! To add to alien, he/she/it could have “tagged” her and just then found her, and the photo was a test to see if it was really her. On a side note, Alien’s Tech could cause this “Feeling” Psychics get from “Ghost/Demons” So it cant not be said that it was not a alien.
borrowed from here.