Okay so this is just a short, crappy one shot I decided to write. Spoilers for season ten.
"Here you go, Cas." Dean says as he places the cup of tea on the table which Cas sits at. Cas doesn't move but just stares down at the table, hands in his lap and hunched over. "What's wrong? You've been so depressed lately." Dean walks behind Cas and places his hands on his shoulders. "Are you in pain?" Dean whispers as he massages Cas' shoulders. His husband just sighs in response, as in 'of course'.
"I was supposed to be the one that watched you grow old." Cas says. "I was going to take care of you... a-and it would've been okay when you died because I would've just stayed in heaven with you. But now... I'm going to die and you'll be left alone miserable with-" He runs out of breath. When he gets it back he continues: "With that stupid Mark." The ex-angel's voice cracks. Dean leans forward and sees a tear rolling down his crinkly face. "Hey," Dean moves beside him and kneels down. He's perfectly fine before he looks into those damn blue eyes. The same eyes he saw in the barn when he first met Castiel. The ones he pleaded to when Cas was about to kill him. The ones he looked into when Dean was about to kill Cas. "Oh, Cas." Is all Dean manages to say as he places his hand on top of Cas'.
"I'm sorry Dean." Cas' eyes flutter.
They knew Cas didn't have much time left. They knew for months. Dean thought he was prepared, he thought he was ready for it. The mark made him feel less feelings so he thought it wouldn't hurt. He was terribly wrong.
"You're okay, right? You're fine. Drink your tea, Cas. Drink, please. You need to drink it."
"I can barely move Dean." He mutters. Dean shakes his head at him and presses his lips together. "You're lying. I know you are, it's just another one of your jokes."
"Dean..."
"Shut up. Drink your fucking tea. Drink goddamn it!" He's screaming now.
This is not how he planned it. He didn't want to scream at him, to make him cry more. He wanted it to be sweet and humble and loving.
"Dean, I can't- ... I can't breathe-"
Dean stands up and loses it. He swings his hand and it smashes the cup of tea off the table, splattering tea all over the wall and floor. Dean's whole body is shaking now and the mark is screaming and burning.
Cas' head falls to the side as he fades away. "Stop-" He barely says before his mind shuts down.
Dean turns back around and Cas' eyes are the slightest of open and are dazing off onto the ground. He's completely lifeless now.
"Cas?" His voice cracks. Tears flood his eyes now and he feels like if a feather landed on his shoulder he would crumble into dust.
"No. No. No. Why. Cas, I- ... I need you Cas. I can't..." He falls to his knees.
Scenes flood in his mind, from sixty years ago to six days ago.
Every smile, every kiss, every night, every drive. They were all special and amazing. When they confessed their love. Their first official date. Their wedding. And now he's gone. All those moments are now nothing, they don't exist. Dean has to live the rest of his life, the rest of the world's life, without him now. It's not possible is it? No.
He didn't even get to kiss him one last time. He'll never be able to kiss him again, never be able to hold his hand, be able to make him tea in the morning, nothing. He's gone. It's not real though. Right? It can't be. It's a dream, it has to be. A cruel, cruel dream.
Dean lifts his head up and looks at Cas' face again. He can see the young man he once knew still. And he could picture his wings spread out. He was so beautiful, he is so beautiful even with his gray-white hair and wrinkles.
"Why did you leave me, damn it? I loved you Cas why?" He crumples into Cas' lap, knelt over him and weeping. The pain is unbearable.
He'll get revenge for this. Even if he has to kill the world. He'll get him back somehow, someway. He can not live without him.
