It was not his first time in Hell. In the early days, when God had banished Lucifer from Heaven, a balance had to be established between the two opposites of the Universe. At first, when only Lucifer had roamed in the Pit, it had seemed manageable. Heaven still commanded three Archangels against the single, fallen one.
But then, the Devil started creating Demons. Malicious, bloodthirsty creatures that were not limited to the barriers of Hell like their master. They crawled unto Earth, and clawed at Heaven's gates, though never breaching them.
Earth became a battle ground. At times quite literally, but most often the battle laid within the souls of human race. Between faith and corruption. Selflessness and sin. Good and evil. Which path would the humans choose, and where would their souls be sent for eternity?
When it would come to a physical altercation, the Angels would throw the Demons back in the fires of Hell, chasing them into the flames as the filthy moths they were. On these few occasions, Castiel had set foot in Hell, though barely crossing the border once the Demons were back in their place. The Angels may not have feared the common Demons, but any sensible Angel feared an Archangel, especially one as twisted as Lucifer, and thus stayed out of his reach.
At some point - a long, long time ago - they seemed to reach an equilibrium, maintained by the decisions of humankind, sending some souls to their torment and others to their bliss. Heaven had almost retreated back from interfering, letting God's creations make their own choices.
This was the first time he had ever been so deep into the burning dungeons. They were surrounded by Demons who ripped at their graces to push them out, knowing why the Angels had stepped so deeply into Hell for the first time ever, trying to keep them from their target. Despite the ongoing battle, he couldn't help but to notice the seemingly eternal rows of cages, hallways without ends filled with desperate screams. It was incomprehensible to him why so many humans would follow a path that would lead them here.
The more Demons that surrounded them, the closer they knew they were getting. The Demons' desperate moves revealed the route for the Angels to follow.
It was a coincidence that Castiel reached him first. An opening occurred, and he followed the order that all the Angels had received; Retrieve Dean Winchester.
When he stepped into the cell, he didn't recognise the supposedly righteous soul. Instead, he found a dark and crumbled creature standing next to a rack, where another lost soul laid screaming, a crimson blade twisting into the reanimated flesh. The humanoid shape had been summoned, not to recreate the human it once was, but to encompass the soul in a vessel that would inflict the most devastating pain.
The creature stopped its actions and turned towards the new, unknown light in the pitch-black cell.
Only then did Castiel recognise the tormented human soul.
And recognised that they were too late.
For a second, in an abnormal rush of disappointment, he considered turning around and leave the lost man in his cell to rot. How could he have given in so quickly, so easily? He had broken like a twig, possibly unleashing Hell on Earth, and now stood as nothing but a shadow in the darkness, his body skinny and blackened by layers of blood. Despite the prophecies, how could he possibly be the key to stopping Lucifer?
But then, he looked into the creature's eyes. Still green, even in the dim light and under the layers of grime that covered the face.
He saw the despair. The self-hatred. The confusion. And barely there, a little spark of hope. Even though this human did not know what it was seeing, despite being broken to the point of unrecognizability, it found careful hope in the simple light in the darkness that Castiel constituted of. And it resonated in the soul, making the light flicker in answer, seeping through the cracks of darkness.
If this light could survive in the darkest pit of Hell, despite being tormented and broken, twisted from its own ideals, well-knowing what it could become, then Castiel could put his faith in the prophecy, in his Father and in this crippled soul.
He stepped forward, and the soul shied away from him. Despite the speckle of hope, Hell – and possibly the life of a hunter – had taught it never to believe that anything good would ever happen to it again.
No time to waste, Castiel rushed forward, not caring that the soul scattered into a corner, and grabbed it by the arm, summoning his grace to cleanse and raise the soul to its former corporal vessel. As the soul disappeared into golden light, leaping out of its cage, Castiel send out the message; "Dean Winchester is saved".