Difficult though it might be to see, you're going in the right direction. With every step you take, the fog gets thicker, the air gets chillier and the screams get even louder. Whether this provides a sense of comfort or not doesn't change the fact that you're getting closer to the victim and closer to whatever is making the victim scream...

The Ventus Jinx seemed to have worked in your favour; the jet of wind from your wand is enough to clear away the fog surrounding you. As it thinned, you can make out two figures up ahead: one lying on the floor and the other hovering above it. The scream was coming from the tear-stained face of the young male on the floor. The fog cleared some more and you are able to see... it.

There was no mistaking the strong stench of decay coming from the cloaked figure. Through the sound of the screams, another sound was starting to fill the air. The creature drew in a deep, rattling breath, as if it was trying to breathe in as much of the human as it could. A hand reached out from under the cloak; a scabby, rotten hand was reaching forward, as if it wanted to grab the victim... to feast on it...

If you're observant enough, you might have noticed another feeling settling in from the very presence of this creature. A strange feeling of despair and hopelessness...