Into the Darkness

Mark crept up the stairs to the attic door, skipping the creaking floorboard.
"Let's just get this over with," he thought.
He was just keeping his word, after all. At the time, sleeping in the only house of the neighborhood wasn't scary, even if it was rumored to be haunted.
When he made the promise, he was confident, but now, his hands would not stop trembling as he reached for the doorknob. The door creaked open, and Mark was pulled inside against his will.
"Huh. This isn't so bad," Mark said.
He propped a pillow up against an old bookshelf and dragged over a blanket for comfort. Mark was sure that he would make it through the night.
But that was not to be.
As soon as Mark closed his eyes, unafraid, a dark figure tightly clasped it's hands around Mark's throat and pulled him into the darkness of the attic.
A long, sharp knife glistened in the moonlight, and in a split second it was covered in red liquid.
Mark was never seen again...
And neither was the dark figure...