There is dark energy on the other side. I think the term evil is subjective but it is very clear that there are energies that thrive on making people miserable. Just as there are humans here who do the same thing. It can be as simple as when miserable people die that misery traps them here and they continue to get a kick out of keeping it going. I'm sure there are demonic forces out there too but I haven't encountered them. There are also something called shadow people (I think) which is what I've had for as long as I can remember until I cleared them out recently. These seem pretty powerless but I think things can get pretty bad depending on the entity.