Fear
Dean sat in the chair, staring at the tubes and wires coming out of his friends body. It was his fault he was here, hooked up to those machines. Cas did everything for him. And now he was a vulnerable human, and could die, and it was all Dean's fault. It's not like Dean didn't already blame himself for what happened to his dad, to Ellen, to Jo. But somehow this was different. Castiel stirred a little and slowly opened his eyes. He was confused, and Dean was sure he saw a spark of fear in his eyes. But then his gaze landed on Dean and the fear disappeared. Dean smiled a little.
"Hello Dean," Castiel greeted.
"Hey," dean replied, his voice cracking a little. "You all right?" Castiel looked down at himself, surveying all the bandages and the tubes.
"I don't know," he finally said, turning back to Dean. There was some panic in his eyes and Dean felt as if he was going to suffocate. It was all his fault after all, damnit.
"Hey, it's okay," he said, masking his own grief. He had to be strong for Cas. He had to let him know it was all going to be okay. "They're just going to wheel you into a room, give you something to make you sleep, and fix you up," Dean said, lightly patting Castiel's hand. Castiel looked panicked for a second.
"They're going to operate on me? Is it safe?"
"Don't worry, none of the doctors here are ghosts. I checked." He made extra sure the nurse in charge of Castiel wasn't a monster the moment they got in. He even threw salt into her face and said "Cristo" to her a few times until she got weirded out and left.
Castiel seemed to calm down when Dean said that. He relaxed into his pillow and looked up at the ceiling.
"Is it strange that I feel afraid?" Castiel asked quietly.
"Afraid? Cas, why?" Dean asked, puzzled. Castiel slowly turned his head to look at Dean.
"Without my powers, I'm, what was it you called me? A baby in a trench coat?" Dean chuckled a little.
"And it's true. I'm useless without my powers."
"No, Cas," Dean shook his head. "You are not useless. You're-"
"Dean, admit it. I am useless. If I die, or become crippled in this weak body I now possess, who will take care of you? Who will stop Fate or Death from taking you too early?" Castiel asked quietly. Deans jaw fell open, and he was silent for a long moment.
"Cas, you don't have to worry about me, I'm a big boy," Dean said, smiling. Castiel turned his head away, shaking it a little.
"Right now I'm more worried about you," Dean continued. He realized that his hand was still resting on Castiel's where he had patted it earlier. He quickly retracted his hand, his cheeks turning red. The action made Castiel look at him again.
"Uh, sorry," dean stammered, looking away. After a long silent moment, Castiel turned his hand palm side up.
"I am also afraid of this surgery thing. And I'd feel better knowing you're here," he said. It was a lie of course. He wasn't scared of the surgery. He was scared that he would wake up and Dean died or got seriously hurt. Castiel was so worried that if Dean's hand wasn't in his, he'd disappear. And Castiel wouldn't be able to bring him back. He wouldn't be able to heal him or revive him. He'd be gone for good. But if he needed to pretend to be scared of a surgery to get Dean to hold his hand, then he was okay with that. And Dean did hold his hand, thinking he was calming Castiel's nerves, not knowing the giant leap of faith Castiel took in him when he was finally taken away for his surgery. As always, Dean was oblivious to the prayers Castiel said, the prayers hoping that Dean would be strong and survive another day, and be there when Castiel opened his eyes again to this still new, strange human life he now led.