Have I Changed My Mind About Demons?

Have I Changed My Mind About Demons?  I'm always trying to learn and think of things differently.  Demons are a complicated topic.   Most people believe that Demonic entities never walked the Earth in human form, but what if that isn't the case at all.  Could this be a case of mistaken identity?  What if grumpy and evil people in life spend their afterlife tormenting us and trying to harm because they are just evil individuals, not fallen angles that aligned themselves with Satan.