I find that some things can intrigue a person so much that they start to believe it as truth. not saying that this is the case for you but beliefs are often not absolute and final because of this thin line between fantasy and reality.
I believe such beings can exsist I'm sure they do but I more readily believe they exsist in a seperate world than ours and if they exsist here it's not in the way shape or firm everyone pictures and imagines it's much less glamorous.
It sounds crazy but I think they do too, but they're not like we expect. They're better at hiding. For all I know, I've been drank from and they made sure I never remember, but I do believe.