Dean Winchester had a death wish and everyone knew it. Even Castiel knew it, and he rarely figured out human emotions, but the despair he could see in Dean's eyes made it clear.
Dean wanted to die.
Castiel placed this fact in the back of his mind, never forgotten, but not at the forefront, not when they had an Apocalypse to avert. Castiel knew Dean well enough to know he would never intentionally hurt himself, because that would mean leaving Sam to say no to Lucifer alone.
Nevertheless Castiel watched over him during his battles with various monsters. Sometimes he would see Dean hesitate, not making the end move when he had a perfect opportunity, instead letting the fight drag on, maybe giving his opponent time to fatally injure him.
Maybe Dean wouldn't kill himself, but he might allow himself to be killed.
Castiel had been watching Dean for a long time, longer than either Winchester brother knew. He had seen the way Dean had quietly suffered after his father had sold his soul to save his life, he'd seen the way Dean had jumped at the chance to do the same for Sam a year later. And Castiel had seen the way Dean had handled only having a year left to live. Most people would have spent it doing things they'd never been able to do before, or they'd just be content with their loved ones.
Not Dean. He threw himself into the hunts, becoming more reckless than ever. It was almost as if the year he had in front of him was too long, and he was looking for a quicker escape. But he survived until his time was up, and the Hellhounds dragged him to Hell. Then Castiel raised him from perdition, and Dean went right back to his old ways.
So Castiel watched. The fights that Sam were not around for worried the angel the most. He could see that Dean knew it would be the perfect opportunity for something to happen to him, because Sam wouldn't be around to stitch him up, or rush him to the hospital. Castiel knew it was only a matter of time until Dean took advantage of that.
Castiel was right. One cold December night Dean was walking from a bar back to the brother's motel room. Sam had the impala, and he was off following leads on the shape shifter they were hunting. He wasn't going to have any luck though, because the shape shifter was following Dean.
About a block from the motel, the shifter attacked. She had a wicked hunter's knife that she planned to slit Dean's throat with. But Dean hadn't managed to live this long without good instincts. She struck, but he spun, grabbing her arm and twisting her wrist until she dropped the knife.
"What is with you shifters and your vendetta against me?" Dean asked before swinging a fist at her. In a swift move she ducked, grabbing the knife off the ground in the process. She immediately swung the knife upward, and Castiel watched his fear come true. Dean could've easily dodged the knife, but he hesitated, and then it was too late. The knife slid into Dean's abdomen like he was butter, coming to rest right below his ribcage.
Dean took a stumbling step back and the shifter ran. Dean stared down at the knife protruding from his torso, his mouth open in surprise. He grabbed the knife, yanking it out with one quick pull. He groaned with pain, clasping his hand over the wound, but it didn't stop the blood pouring from it.
Dean collapsed onto the cold ground, and Castiel appeared.
"Cas…" Dean said. His voice was already weak, but he sounded disappointed.
Castiel knelt next to the fallen hunter. "Why did you allow that shifter to stab you?" he asked calmly. He had time to question Dean before healing him, Dean's heartbeat hadn't begun to falter yet.
"What? I didn't. Now heal me will you? I'm bleeding out."
"I don't believe you want me to heal you Dean."
Dean coughed, and a little bit of blood trickled out the corner of his mouth. "What are you talking about Cas? Just heal me."
"Tell me why you let her stab you and I will heal you."
Dean coughed again and more blood came out. Castiel felt Dean's heartbeat begin to slow, but he still had time. Dean stared at the angel furiously, but the angel just stared back. Dean closed his eyes in resignation and began to speak. "Because, Cas, sometimes… Sometimes I hope I don't make it out of a fight. That way I'll die a hero, and Sammy can be proud of me. I want to die sometimes Cas, but I can't do it myself." He looked Castiel in the eye, as if daring the angel to judge him. Then his eyes rolled back and his head hit the pavement. Castiel had gotten distracted and let his heartbeat get too slow, and now he was unconscious.
The angel placed his hand on the bloody wound, healing it quickly. Dean's eyelids fluttered, and he groaned. "Jesus Cas, could you cut it a little closer next time? That wasn't enough of a rush." Cas grabbed Dean's arm and pulled him into a sitting position.
"Explain. Why do you wish to die?"
"That was the blood loss talking," Dean grumbled, unable to meet Cas's eyes.
"No it wasn't."
Dean sighed. "Fine. It wasn't. But I'd like to see you live this life and not want out."
"But you have reasons to stay."
Dean let out a sadistic chuckle. "Yeah, I've got Sam who, let's face it, is going to agree to be Lucifer's bitch any day now. And I've got Bobby, who's about a bottle of liquor away from putting a bullet in his brain. I've got no reasons, Cas."
Castiel cocked an eyebrow. "I see that I mean little to you."
"Come on Cas. We both know you only trail me around like this because you don't want the apocalypse to happen. You wouldn't keep saving my ass otherwise," Dean said bitterly.
Castiel blinked with surprise. "Have you forgotten that I rebelled against Heaven in your name? I save you because I do not wish for you to die. I care about you Dean, not your involvement in the end of the apocalypse."
Dean was silent for a moment. "I'm sorry," he finally whispered. Castiel was unsure if he was sorry for doubting him, or sorry for allowing himself to be hurt, but Castiel took the apology. He laid his hand on Dean's shoulder and they were instantly back in the cheap motel room.
"Look, Cas… Can we not tell Sam about this? I mean, I'll tell him the shifter jumping me, but, y'know, not the other stuff, ok?"
Castiel nodded. "You should know, I'm going to keep an eye on you. I do not wish for this to happen again." Dean smiled and nodded.
"It won't."