Disclaimer: All Harry Potter elements in this story belong to Rowling, who I am still holding a grudge against. I am not making any profit from this story. I just love Severus Snape. Bite me.
Prolog: Hidden Within
There are deep, dark places in the far corners of one's soul where certain things are hidden. Sometimes those things are there by accident, such as long, lost memories that one simply can't reach or painful things that one pushes so far towards the back of their mind that they fall into these hidden place.
Severus Snape, however, had mastered his soul, which had been torn apart in the moment he had been forced to kill. He had taught himself to hide things there that he didn't want anyone else to notice. He had even learned to force his emotions down so that when his allies turned against him due to the murder he had been forced to commit, they never saw how much their words actually hurt him. They never saw the real him, which he had hidden away so long ago that he'd almost forgotten he wasn't truly the man he presented to his hateful colleagues. His soul hid the pain for him so that he could survive it without losing his sanity. So that he could complete the tasks given to him by the man he had killed.
The man he had killed had been his friend…or at least pretended to be. He had watched over Severus, but he had ulterior motives. He had used Severus to meet his own ends, not bothering to stop and consider what it would cost him. When the time came, Severus paid the price, killing the man he had trusted most, ripping his soul in two. The man had left him with no escape. The allies that Severus was still determined to help would sooner see him dead than listen to anything he had to say. His enemies, whom he was posing as, secretly loathed him, ready to strike at the first sign of deceit. He was between them with no where to turn. One wrong step would send him plunging towards his death…so he found it easier to leave his humanity behind. Emotions would only weaken him and he thought it would pointless to care for anything or anyone outside of the subtle work he did for his allies, which they didn't even notice. In his eyes, if anyone actually did care for him, they would make fools out of themselves for admitting it. What would be the point in caring when he probably wouldn't even survive the war anyways?
So he hid himself away and no one noticed the he wasn't the man he was making himself out to be.
Or so he thought.