Supernatural does not belong to me in the least! Enjoy!
So tell me now, where was my fault, in loving you with my whole heart?
Why couldn't he understand? Why couldn't his little human mind understand everything that he, an Angel of the Lord, had done for the human race? For him—for Dean, the one he raised from perdition.
There had only been one time when Castiel had been truly angry. That was when he had been convinced that Dean was giving up. That his precious, righteous man had thrown in the towel, made all his work useless. Castiel thought he had failed again. He always failed. He couldn't reach Dean soon enough. Not in hell, not now. That's what he had thought.
That's why Castiel, a creature that was supposed to, for all intents and purposes, be a perfect being with no emotions, had punched Dean in the face. Pinned him up against a wall, screamed in his face. He wasn't going to lose Dean this time. The first time he had seen the man's poor soul, it was tortured beyond belief. He had no connection to Dean then. It was an order. But then he burned his handprint into Dean's shoulder, letting their souls touch in the searing heat of Hell. But this time, this time, he knew Dean. Personally. The man was no longer a collection of facts to Castiel. He was a living, breathing, of import, human. Castiel didn't care if he had to punch the man senseless, scream until his voice was gone. There was no way he was letting Dean say "yes". He would save him this time.
And he had. The apocalypse had been averted. Castiel's grace was restored. And so he took it upon himself to improve Heaven, to make sure tragedy would never rain upon these human with such force ever again.
He told himself it was for the human race. He told himself it was to make sure Raphael wouldn't restart the apocalypse. And it was. All of that was true. It was true of the present him. Castiel remembered he was an angel. He knew he was an angel. He didn't know how different he was. He had become attached. Attached to the somehow still-righteous picture of sin that was Dean Winchester. Dean was the root of everything. Dean was why he cared about the humans. It was less that Castiel loved them, more that Dean did. Not to mention that to his brother's, Dean was no different from any other human. Any danger to the human race as a whole also meant Dean was in danger. Castiel didn't want Dean in any sort of danger. He knew the man would never give up hunting, and he knew the dangers that came with it. But Castiel wanted to protect Dean.
That's why he came whenever the hunter called him. He knew something was bad if Dean dared to look to the heavens for help. So Castiel came. He always came.
The other angels didn't know what to think of it. They didn't understand it. Because they didn't understand it, Castiel was punished for it. It didn't matter. The cycle restarted, and Castiel found himself in the same place, falling ever further. But as long as he could keep Dean from danger, it didn't matter.
After Sam had forced Lucifer back into his cage, Castiel had managed to convince himself that the best way to protect Dean was to leave him alone. To return to Heaven, sort out the problems there, and let Dean live with Lisa and Ben. Something about the whole situation had hurt his chest. It was strange, seeing Dean, but not being seen. There was no danger to protect the "new" Dean from. Castiel found that he wasn't quite sure what to do with himself.
Then there was Crowley.
Castiel thought it would be the best possible way to protect Dean. With that much power, no one could harm his friend. No one would even think of it.
Then Balthazar had gotten it right. Human emotions weren't as unknown to him.
You know the angel in the dirty trench coat who's in love with you?
Love. Castiel didn't really know what that meant. He knew Dean didn't love the girls he came back from the bar with. Want was different from love. Castiel didn't want Dean, not physically. He wanted Dean to be safe; he wanted Dean to never touch Hell again, not even with a very long stick.
Then it had happened. They were searching for Eve, and he was stuck. Powerless. "A baby in a trench coat." Those words had stung. Because it was true. He could do nothing for the brothers. He was a deadweight who followed Dean around like a lost puppy. Castiel didn't want that. He wanted Dean to see him as an angel, someone powerful to depend upon.
So Castiel swallowed Purgatory.
Finally. He had all the power he needed. He could reshape the world as he saw fit. But something was wrong. Dean was angry at him. Dean had wanted him to stop. Castiel felt like he had failed. Again.
Didn't Dean understand? This was the only way. The only way Castiel could win. The only way everything could work out.
Wrong. The word rang in his head. Dean had been right. Purgatory was too much. Dean didn't need or want an all-powerful angel. He wanted a friend to rely on, someone other than Sam that he could trust. And Castiel had broken that trust.
That was why he didn't care. He didn't care when he walked into the water and died. He had failed Dean in the most spectacular way possible.
When he stopped being Emmanuel and before Castiel again, he couldn't help it. He hated what he had done, what he had been. He would have preferred to remain ignorant, just taking pleasure from healing people. But then Dean would have been killed by the demons. No matter who he was, there was a strong instinct to protect Dean. So he did.
Then he took Sam's psychosis into himself. He saw that Dean had forgiven him. So it didn't matter. It didn't matter how much Lucifer tortured him. Dean had forgiven him.
He wasn't a failure.
A/N: So, Supernatural. This was written in an hour, on a whim, and I didn't edit it at all. So feel free to point out grammar/spelling mistakes, and I'll fix 'em! I have so many feelings for Dean and Cas, romantically or not.