i think i may have seen demons before.
when i was a kid, any time i'd get afraid in the middle of the night, i'd run into my parent's bedroom, which was directly across the hallway from my own. on most occassions, i would have to pause in my own doorway before going through because there would be these four beings coming towards me from my parents' bedroom. these beings looked like my parents, my brother, and me in size and appearance, though i could see through them. although they appeared 3D, they looked more like shadows than like anything i could touch. their scariest feature was their red, dimly glowing eyes. yeah, it was spooky.
so anyway, i'd have to pause in my doorway and close my eyes shut really tightly. then, when i opened my eyes again, the things would be gone. once when i was about 8 or 9 years old, i suppose i finally got tired of having to wait for them to disappear. so, i shut my eyes really tight and ran straight at them, yelling the whole way. i ricocheted off the corner of my parent's open door, flew up onto their bed and scared them half to death. however, i apparantly defeated these things too, as they never reappeared.
a couple years ago i found a sight that talked about sightings of these "shadow people", as people called them. people had even drawn pictures of these things, which looked eerily like what i remember seeing. so, yeah. scary.
since then, i haven't physically seen any demons.