This story is inspired by "Exile Vilify" by The National, and by the music "Menu Theme 3". Look them up for added effect:
He had finished his last message, rewarding his work with another bite of an old potato that used to be a battery at one point. It was his only source of nourishment in this place. This place that he couldn't escape.
Despite the fact that the computer that controlled this place was destroyed, he couldn't help but feel that she was somehow still watching. She could be anywhere, and there were still the turrets he had to worry about as well. If only he had a Portal device.
If only he hadn't help to build that accursed machine to begin with.
His travels through the decaying facility led him to discover the old areas, from a time when Cave Johnston was calling the shots. While the experiments in the name of science were no less moral, his ambition could at least be chalked up to insanity.
Whereas that computer, well, she had no conscience at all as far as he was concerned. Unlike Cave, GLaDOS had no reason to further her abstract "science" out side of her own twisted amusement. She had tried to toy with him, but he proved too clever. It wasn't until that girl, the one who didn't talk, did he feel finally free from GLaDOS' iron grip.
Yet here he was, still within the confines. It was strange. He had spent so long hiding behind the walls, that now that he had free reign of the place, he chose to remain unseen. Those small novelty radios that he rigged to transmit signals, in a vain hopes of someone decoding them and finding his message of rescue, were now old and useless. No longer transmitting, but rather, providing company of sorts.
One radio in particular played a tragic song, almost bringing him to tears as he related his plight to the melody. His recent mural also reflected those words. He hoped that girl, the one who he put in the "long sleep" to save her, would wake and end this nightmare once and for all. He also hoped, that before he died, he could see her find one of the murals he painted to honor her.
Companion Cube said nothing to this goal, as always. When it did talk, it spoke in the voice of the turrets that he had grown so used to hearing in the corners and from the shadows. Then again, in his insanity, he couldn't help but wonder if the cube was just him talking to himself, or if it was another form of artificial intelligence cooked up in the name of science.
Finally done with his work, he packed up his meager supplies and moved on to the next area, already planning the mural he would adorn the cold walls with. He could feel the cameras watching, despite knowing that GLaDOS wasn't operable anymore.
There was also the matter of the cores. Once GLaDOS had been destroyed, the others activated in a hopes of freedom, or at least GLaDOS hoped they would come to her aide. However, they didn't seem all that intelligent, really. He had met the one, with the British accent, when he left the subject chambers, after putting that girl in the long sleep. That was the last he saw of that one.
That other one he met though, just wouldn't shut up about space. While he too dreamed of the vastness of the beyond outside these walls, he knew that constantly rambling about it wasn't going to make it come any faster. If anything, it would only make him more depressed.
He vowed to avoid any other cores that may be active, for fear they would report his presence to GLaDOS, if the turrets haven't already.
Dragging his frail body, weak from hunger and dehydration, he made it to the next area that would be graced with his art. Those art supplies he found in that one office, a mere box of crayons left over from some hapless soul of Bring Your Daughter To Work Day, had proven very therapeutic now that Companion Cube stopped talking to him. His meds wouldn't last forever, though. But he knew he would be dead long before that became a problem.
"HellO?" an all to familiar voice asked to no one in particular. "Is AnYOne TheRE?"
He caught himself before he walked into the path of the red beam. He found one of the Weighted Storage Cubes, and used it for cover as he snuck up behind the turret. He smashed the cube onto the robot, sending it falling to the floor, it's beam frantically looking around for it's attacker. Another blow. Then another. Then another.
He stopped when he realized what he was doing. Dropping the cube, he grabbed his things and made his way into the small opening behind the shifting panels. Time to go to work. But as he began, he heard something. Eminating from somewhere, yet managing to project through the whole facility, was a voice. A beautiful voice, singing an operatic aria. As he listened, he noticed the metallic sound to it and frowned.
It was her...singing...mocking him...she knew he was still alive, and that there was nothing he could do about it. The singing continued, the quiet tone adding to the unsettling ambiance.
He curled up on the floor, trying in vain to drown out her mocking. But the song persisted, taunting him back into his madness.