Some things should just be
It was an atrocious act, but it worked. And just like everything else in this world, there was a consequence. This act worked, but not in the way that they wanted it to. They did not take any physical forms. They could talk, but would not be heard. They could touch, but could not be felt. They can see but cannot be seen, even if they were right in front of us. Many visited loved ones. But due to the consequences, they were ignored. Many have gone mad, some fell into depression, and some tried to commit suicide. But you can not kill something that is already dead. Now they walk our world. Walking forever in a world of no communication. At first, no one saw them. Ignored by the world they used to live in. But just like animals, humans adapted to their world through evolution. Soon, we started noticing them. We'd say it was just nothing. Thinking it was just our imagination. Generations passed and we progressed, subconsciously developing our skills to see them. And they have noticed. They've started doing what they can to catch our attention. Giving us chills, whispering something in our ears, in hopes that we at least acknowledge them. Soon, we have come to call them 'Ghosts'. Most feared them, some were fascinated, and few were willing to make contact. The ones who were willing were gifted at birth, as if destiny knew that they would communicate. We gave them the name 'Mediums'. They communicated with the dead, but it has been hundreds of years since they first appeared. Only a few were so willing to communicate peacefully. Don't forget, they were humans once, too. And just like us, they have adapted and evolved.