Depression.

Terrence Mathews, an employee of the Angel Stone hospital starts this story with empathy, and suicidal thoughts. He begins to see hallucinations, going insane slowly. He chats with his friend Adam Clark for a bit while working on a corpse, feeling better afterwards. Adam walks him back, then Terrence goes on to stalk Adam on his laptop, making sure his favorite companion would be alright during the night. Fortunately, Adam is alright, though Terrence finds out a terrible secret of his.