
god decided that humans to be the rulers of the world, there shouldn't be someone above them except gods (i think) dragons are more powerful stronger and bigger than human, demon is someone unholy and something opposite of god and must be exterminated.
If something is untrue that's just my lack of knowledge plus we all know that dragons don'r exist and as for demons it's your choice to believe in them or not because
demons=evil=human (It depends)
...stick with reality...

maybe? I believe in what i was saying and I think what you're saying is also true but for god's sake I don't believe in demons. dragons don't exist and as for why they are killed in manga, film it's only logical it's the people's fear of them or because little kids watch(depends) or read them and there are some people that are sometimes stupid enough to think they really exist and are here next to us. Even i don't believe in god fully to some points, god doesn't decide we decide(that's why we're different from animals) but what nature created cannon be denied. Ok never mind i was saying the answer of your question is FEAR. LOL i think I went too far with my explaining, now I can't understand anything above

i thought you meant entering the story and seeing it with your own eyes and experience the feeling while being a ghost, maaybe i misunderstood it a little bit no big deal :) (and also ghosts are supernatural beings so that probably played the role of me not understanding this) Hey hey I'm just a little girl whose native language is not english (≧∀≦)
Why do humans kill Demons! Why do they kill Dragons!?! Because they are 'monsters'?
The real monsters are humans. those who claim intelligence and use it for... well to put it simply, crap.