((This is kind of my little reaction to season 6 finale- major spoilers here, so just don't read if you care at all about preserving your innocence about what happened. I don't mention details here, but you get the gist... I just wanted to write something from Cas' POV... again, this may end up being a series if I get enough of a response to it.))
xXXx
There's no time to explain, nor to ask for forgiveness. Not that it'd matter, you wouldn't listen to my explanations and I don't want your forgiveness. (That is a lie- as you were so fond of pointing out- I'm a terrible liar.)
Even now, if I came to you, you would listen. Not until you tried to hit me a few times and berated me on the foolishness of my actions (as if I couldn't see that in every painfully vivid detail of the aftermath.) But in the end, you would have listened, and maybe if I had asked for it, you might have even forgiven me. But even if I had the time to sit down with you, I wouldn't ask. After all that I have done, the last thing I deserve is your understanding.
How I wish I had never stepped down this road. I did so believing that I could set your world right, to make your sacrifices mean something. How was I to know that it would lead to this? That I would become your last great struggle, that I, of all people, would be the one to betray you. I was meant to be your guardian, and I wanted to be your friend.
I wanted to protect you.
… Was this what you meant by irony? If so I do not understand the appeal. It is so very… bitter. To think that this is how I would end my days… alone. Hated by those who I care about. No chance to explain.
And we're back to the beginning. It seems that my dying brain is just running in circles. Perhaps now is when I'm supposed to say something to sum up my life; my choices, my victories, and this… but I've got nothing. So I suppose, since I cannot see you in person, I can remember… and well, there is always prayer.
Not like that helped. Ever. But who knows, perhaps my final sentiment will get back to you somehow, so that you'd know that I died with your name on my lips.
I don't deserve your forgiveness... But, Dean?
… Please forgive me…