It was risky, incredibly so, but what other choice did he have? He had been wrong, so very wrong, to say yes; he had underestimated Lucifer's strength after he had already felt an archangel's power more than once, and now he was a prisoner in his own body (Jimmy Novak's, he tried to remind himself, but over the years he had lost the ability to distinguish between his vessel and himself).
But amidst the despair of watching Lucifer interact with his friends, of praying to their Father when he saw Dean hesitate, flinch as Lucifer touched his shoulder – let him notice, let him know – he remembered that he was, or at the very least, had been a soldier.
He had fought too many battles to give up. This was another battle.
And he had to win.
He couldn't openly try to regain control. Lucifer would easily knock him out or kill him. He probably only hadn't yet because he enjoyed Cas' suffering. Which meant he felt what Cas was feeling.
So the first step was to withdraw. Gently, slowly.
His instinct screamed against it – if he withdrew, he couldn't see what was going on anymore – but he had no choice. It had to be done.
Lucifer had to get used to receiving nothing from him, no impressions, no feelings. He would think Cas had given up, and would grown bored. Already, he was barely talking to him. He had done it quite frequently in the beginning, taunts that meant nothing to Cas because he had accepted the truth long ago.
They really don't care for you.
Dean really looks weirded out when I – I mean you touch him. Guess he doesn't like it when you're close.
It's been three days. The only call you when they need you.
There had been a time when he had thought he meant something to the Winchesters. That time was long gone. Lucifer couldn't hurt him now.
Cas concentrated on beating him, on withdrawing, on meditating deep inside himself.
Once enough time had passed, once he felt sure Lucifer had all but forgotten about him, he began.
Lucifer would, in due course, kill Amara. Cas was ready to die for that, to save the world. To save Dean. But what the freed archangel would do afterwards...
Cas had to make him stop wanting to lead a war against Humanity. There were too many angels left who would agree with him.
So he had to make him experience emotions, had to make him see everything earth had to offer, and Lucifer had to believe it came from within himself. It would be difficult.
And he would have to use the most powerful emotion he had ever experienced.
He didn't want to. He had buried it long ago, sworn never to reveal it to another being. But Lucifer knew anyway. Every angel he had ever met knew.
Castiel loved Dean Winchester. His love would never be reciprocated; Dean saw him only as a tool to be used; and yet he loved him.
He had to make Lucifer believe he loved him, too.
And so, he let his emotions slip through the wall he had built between himself and the archangel again. Slowly so that Lucifer wouldn't notice he was suddenly getting impressions from Cas again, so slowly that he would believe they were his own emotions.
It felt wrong, everything about it felt wrong, but there was no other way.
Cas had formed this weird habit of staring at Dean.
He realized how stupid that sounded, but Cas' stare had always been... different.
Not like this.
He'd always looked at Dean as if he was something fascinating, or as if he wanted to help him, or as if he just wanted to spend time with him (a stupid thought really, considering CAs always left, but that was how Dean had seen it, before – well, everything and he was tortured with half-buried thoughts of might have been, perhaps).
Now, though –
There was something hungry in his gaze. Something feral.
Dean didn't like it.
Sam only chuckled when he told him, and when he demanded an explanation, his brother laughed.
As if he knew something Dean didn't.
But if Dean knew something, he knew when Cas was being Cas, and when he was being weird.
And this was him being weird.
And it sucked because suddenly, the angel was always there.
He was still working on how to get rid of Amara all right, but the bunker was very much his base at this point. He showed up every day. And he always went straight for Dean, asking if he could help make dinner or watch a movie with him.
In short, it was everything that Dean had always imagined a good hunting life would look like – well, minus Amare. But he could deal with that for now.
What he couldn't deal with was the strange vibe he was getting from Cas. It was almost like the time he had been controlled by Naomi; but certainly there were no feathered bastards pulling his strings now? They knew it didn't work. And Cas wouldn't make the mistake of working with Crowley behind his back again.
And of course Sam denied everything.
"I'm telling you, Dean, we're not doing anything behind your back! If you could just man up and admit what is really wrong, maybe you wouldn't – "
"Calm down, Samantha, it was only a question." He rolled his eyes.
So, no lying there either, then.
But what was wrong? Because something was. Every instinct he had was screaming that something was wrong.
And it had all begun when Cas touched the wrong shoulder.
It was stupid, he knew. But Cas only ever touched his left shoulder. Where his handprint had been.
And his words, too – this could be a good thing. The Cas he knew would never have said that, not when Dean was freaking out.
He tried to subtly observe him whenever he was around, and with how much time they spent together, it became easier and easier.
But he still couldn't put his finger on what was wrong.
It was working. Through small glimpses, Cas saw that his plan was working. Lucifer was spending more and more time with Dean, and the side of him that had become more and more like a human rebelled at the sight. The devil could do what Cas had always wanted, could practically live in the bunker and stay at the Winchesters' side.
It was ridiculous to be jealous of Lucifer. That didn't change his feelings, however, and he had to control his emotions even more than before. Because if Lucifer felt his jealousy and realized where the desire he was following was coming from...
And so he watched as Lucifer pursued Dean. At this point, he had apparently admitted to himself that he wanted this human, and he didn't even think it weird.
Cas had done well.
He wished he could be proud of it.
But thankfully, not only was Lucifer losing interest in his other plans to be near Dean, but Dean began to notice.
Because he couldn't stay and watch for long, it took Cas a while to notice, but when he did, he could only send out a prayer of thanks. There were signs that Lucifer couldn't read, but that he recognized immediately after years he had spent studying Dean Winchester's face.
Dean was suspicious.
Dean snuck glances at him, worried glances, confused glances. Now and then, he asked questions that Cas knew had a hidden meaning in them, as if he expected him to reveal something; and every time Lucifer reflected, Dean's eyes became sadder.
Dean knew. Dean knew and Dean would do the right thing.
His death meant little to Cas.
As long as the Winchesters survived, he was happy.
Dean was seriously starting to worry.
At first, he had thought something was wrong, but over the last few weeks, a conviction had grown inside him, a conviction that made it difficult not to take a step back when Cas invaded his personal space, sat down on the couch next to him or even followed him into his room because he "wanted to talk."
This wasn't Cas.
The little weird touches to his behaviour that Dean had observed in the beginning had smoothed out, so that he was mostly acting like Cas now.
But this wasn't Cas.
He knew Cas. He didn't know this thing.
But what could it be? Not a shapeshifter or Leviathan. Dean might not have been the brightest, but he would have noticed if a monster had tried to pass as his best friend.
But then –
Dean's hands stilled. He had been cleaning his guns, the process always helping him think.
CAs had been in –
No. Please no. Anything but that.
He couldn't be spending time with Lucifer, surely? It couldn't be Lucifer looking at him like that.
He breathed a sigh of relief. That was true. Lucifer thought them all mud monkeys. He wouldn't go out of his way to spend time with a human. At least that was off the table. But then what could it be?
He'd have to do some research.
It wasn't easy. These days, Amara was always singing her siren song somewhere in his head, making it hard to focus.
But this was Cas. He had to try. For Cas.
He felt it when Lucifer decided to take action against Amara, and furthermore, he felt why.
His whole body was vibrating with the need to get rid of a threat.
It had been one of those days that were becoming alarmingly frequent, with Dean obviously stopping himself from going after Amara, their bond forcing him closer.
And Lucifer was jealous. Lucifer wanted Dean for himself.
Cas prayed, as Lucifer plunged the blade in her and his Grace sang with triumph, that he hadn't made his biggest mistake when he had let him feel his love for Dean.
It was weird as Hell. One minute, he was helplessly babbling to Sam, who had cuffed him to the kitchen table since it was one of his best days when all he could hear in his head was Go to her, and the next, there was peace.
He sat at the table and the longing he'd felt was just... gone. If anything, thinking about it made him feel slightly nauteous.
"Dean?" Sam asked.
He shook his head. "I'm good."
"Really?" Sam asked, clearly sceptical. Maybe he thought it was a trick.
"Yeah. I don't feel like I have to find her anymore. Well, I'd like to gank her, but that's it."
Sam studied him. "That's – "
"Amara's dead" Cas declared, appearing in the kitchen, a triumphant gleam in his eyes.
And now even Sam realized something was wrong. His eyes went from Cas to Dean and back again, because the angel was looking at him with a hungry expression that didn't fit their friend at all.
"Can I talk to you, Dean? Alone" he said, and Sam wanted to protest when he saw Dean reach out to him, just a little.
"Of course, Cas. You just saved the day, didn't you? Pretty much nothing I wouldn't do for you right now" Dean answered, uncharacteristically demure, but it seemed to be what Cas wanted to hear because his expression turned into a leer.
Sam swallowed, but as his brother allowed Cas to lead the way to his room, he made a circle with his hand.
Holy oil then. Sam quickly went to get it.
"So, Cas. Thanks. You've no idea how good it feels" Dean said. He played up the whole saved-damsel-in-distress-thing because he figured whatever or whoever had control over Cas liked that sort of behaviour and he was right, because the – not his, this wasn't his – angel stepped closer, grinning.
"I can think of a way to make it feel even better."
And then his lips were on Dean's –
And this was not what he had allowed himself to dwell on only when he was half-asleep, in forgotten dreams where he could actually have what he wanted without feeling guilty –
No. This wasn't Cas.
But if he made a scene...
Dean gently forced them apart and looked into eyes that were much too dark for Cas to be looking out of them.
"Who are you? You're not that annoying angel" he said, hoping his lie would fly.
It did. The thing grinned and brought his hands up to rub Dean's sides. He managed not to flinch.
"You've known for a while, haven't you?"
He tried to appear unconcerned as he answered, "Sure. Wouldn't have wanted to spend that much time with Cas".
"That's what I told him."
Dean's heart beat faster. Cas was still in there. It was what he had been hoping to hear, and why he had signed to Sam that they needed holy oil. Cas inside would probably ensure that it held whatever this was captured...
That was if it wasn't after all –
He had heard that tone before. That mocking tone.
"Lucifer" he breathed. The devil grinned lecherously at him.
"Exactly! I'm back baby and I'm waiting for my reward for killing Amara" he pressed his body against Dean and Dean forced himself to lean into him, act like he was enjoying it. For whatever weird reason, Lucifer wanted him, and Dean would use that against him.
Cas. Think of Cas.
He brought his hand up and played with Lucifer's hair.
"You can have all the rewards you want, and more. But can we deal with Sam first? He'll be so annoying..." He whined, hoping against hope that it would work, and to his astonishment, Lucifer happily agreed to get rid of his one true vessel.
What was going on?
Cas. This must be Cas' doing.
"I could change. Take him instead. But you probably don't want that."
"Sorry". He gave the devil his best puppy dog eyes. "It's not that I don't want you, but he's my brother. It would just be awkward."
"Don't worry Baby, I understand."
As they passed into the living room, Dean saw Sam throw down an match and jumped away from him.
In the next moment, Lucifer was howling and screaming, ordering them to let him out.
"You alright?"
"As well as I can be. He – " Dean shuddered. "He came unto me."
"What?"
He shrugged. "He thinks he wants me. I think Cas is behind it."
Lucifer, of course, heard him, and Cas had him so dosed up with lovey-dovey thoughts apparently that instead of getting angry, he actually started waxing poetry.
"But Dean – I can love you so much better than Cas ever did– he doesn't know how to make you happy – "
This was definitely one of the creepiest moments of Dean's life.
Wait, had he just said Cas –
It didn't matter. They had to concentrate on something else right now.
"Didn't you say you'd found a spell to tear angels out of their vessels?"
Sam nodded. "I just don't know what it will do to Cas."
"We have no choice. If –"
It was at this point that Lucifer exclaimed, "Oh, Cas, is it? No, he won't have you!"
And then Dean saw the angel blade in his hands.
"NO!" he screamed and, before Sam could stop him, he'd jumped into the circle.
"It will kill you too – "
"Two angels in a vessel, Dean. A loophole. If I plunge the blade into his Grace and not mine –"
And Lucifer raised the blade.
Dean quickly pressed his body against Cas', the blade between them.
"But Lucifer – "
Lucifer still thought he wanted him, he could tell.
He looked into his eyes and prayed at Cas.
Cas, he has to be on top. I'm gonna put that blade into your chest, that's where he has to be. Please, Cas.
Dean was praying at him. Cas knew what he was trying to do. He didn't think what Lucifer had said was true; he believed he'd managed to confuse the archangel so much that he believed he could kill Cas without hurting himself; but still he had to try. For Dean.
And as Dean twisted the blade, Cas attacked the Grace that had been holding him captive for months and twisted it, brought it to where the blade could meet it.
And everything turned black.
Cas was surprised when he woke up. He had been certain he would die.
He was even more surprised when he realized where he was.
"Cas?" Dean steered next to him on the hunter's bed. "I wanted to watch over you. Was too exhausted, apparently. Sorry."
"I don't mind" he replied for lack of anything else to say.
"You don't?"
"I never did" he admitted, too busy to check his words as he realized that yes, he was alive, yes, he was human, and yes, he was indeed lying next to Dean in his bed and the hunter had no problem with it. On the contrary. He moved closer.
"Cas, Lucifer said something... He said he would be much better at loving me than you ever were" he shuddered involuntarily before continuing, "and I was wondering – do you? I mean, like me? Like, would you stay if I asked?"
Cas reached out and took Dean's hand, the knowledge that he was seeing in the hunter's eyes was love making his own tremble, "Yes. I always wanted to stay." He paused then asked, because he had to quench the suspicion in the back of his mind, "You didn't mean – "
"God no. Just had to keep the creepy son of a bitch from guessing the truth."
And there was nothing but honesty in Dean's eyes.
As their lips touched for the first time, he knew that finally, after all these years, everything was alright.