Demons are supernatural beings, they are a completely seperate thing from human. While it may be possible to be possessed by a demon, you cannot be a demon, at least not in your physical form.
YES! very real
Yes!
No, but mental illness is real.
Well no
yes
yes he is
speed demon checkered boars are the best yes its real
Well no people's there are not real
yes
yes
Absolutely Not
Yes Demon spirits are real.