“Not extraterrestrial, interdimensional.
Demonic beings that do not come in the name of peace, but to deceive and destroy.”
We don’t need to go to a different dimension to find demonic beings. We got all we need in this dimension.
We can't go there, (well, maybe one time only) but they can travel back and forth.
Same with benevolent beings (angels) - they can travel back and forth, but we can only go there once (forever).