Castiel had promised. He never broke his promises. He was sat in a park, the same park he had once sat in with Dean. People walked past him with worried expressions but he barely acknowledged them. Instead his attention was solely focused on the envelope in his hand. He'd carried it around for thirty years now; it was battered and torn but never opened and rarely touched. This envelope weighed more than his heart. His fingers shook, he had to open it, he'd promised. Castiel took a deep breath (he'd become to attune to human habits now) and gingerly opened the envelope. He unfolded the letter inside and began to read…

"My Dearest Castiel.

Is that too corny already? You know I'm no good at writing but this is important. Unless you broke your promise I believe the only thing I can say is I'm so sorry Cas. I hope it's many years in the future you're reading this and not a few hours after I write this damned letter. I just need you to know how much you mean to me and because I'm full of pride there are things I'll write here that I would never say out loud. But you need to know them. All of them.

Let me tell you about when we first met, when you stormed into the barn, taking round after round from our guns. You looked like a human but the shadow of your wings telling a different story. You were nothing I had ever seen before and I was in awe. You told me everything, from raising me from perdition to putting my body back together. Castiel, the angel of the lord, went to hell for some hunter. I never deserved it and deep down you knew that. Then all hell broke loose, literally; through all that time though, you were there. You stood by me, you knew why Sam was important to me even when he was doing wrong. You believed in me Cas, when no one else did and I could never thank you enough. Did I ever tell you the story of how I fell in love with you? I must have at some point in our lives but I'm going to tell you again anyway.

The day you came to me with Uriel and requested I torture Alistair. That's the day I fell for you. Now, before you think I'm all fucked up in the head I think you can remember when happened after that. We were hurt, we were all hurt and we were both scared to death of Sam. I remember lying in the motel bed that night, sobbing. I'd had to relive hell, learn my brother was a monster and watch you get hurt all in a day. I was so messed up that day; the tears just fell and never stop. Until suddenly there you were sitting beside me in that creepy non-moving way that you do. You looked at me, looked at the mess I was and without a single word you lay down next to me and held me. All night Cas you stayed all night holding me in your arms. I loved you from that moment onwards.

Our relationship grew pretty fast huh? I'm laughing as I'm writing this, remembering all the times Sam's caught us 'making love' as the sap would say. I knew he was happy for us though. Happy that I'd finally done something good with my life.

I would like to thank you Castiel, for being there every step of the way when I lost Sammy. I honestly believe if it hadn't been for you I'd have been dead a few hours after Sam. But once again, there you were. You held my hand while I drove to nowhere, you allowed me to destroy part of a forest and then held me for hours afterwards as I shook violently with tears. You were there for me when you should have been in heaven but you never left me. Not once. There are no words great enough for you Castiel.

As I write this, you're out at the Impala. I have no idea what you're doing but the hood is up and I swear to god if you ruin her engine you should run! Do you remember the night we lay on the hood and star gazed all night? I'm going to do that again tonight, that's when I'll give you this and I'm sorry if it's been a burden for you Cas. However you had to know all this, you have to know that even though I'm dead I still love you.

I hope I live a long life with you Castiel. I hope we spend every second together and fill our lives with love.

Most importantly, I promise you I will see you again. You may be the angel on earth and I may be the hunter in god knows where but we will find each other again.

So live your life Cas, don't worry about me. I'll be waiting.

I love you Castiel. Always and forever.

Signed

Dean Winchester