Author's Note: Here, we have sick!Cas, possessive!Dean, a mental breakdown, and all kind of angst. Sounds exciting, doesn't it?

Though there was obvious tension brewing in the bunker (Sam trying fruitlessly to convince Dean to let them change him back into a human, Dean threatening to leave and never return if Sam tried to use actual force against him to make that pipedream come true, Castiel trying to pretend everything was alright when both his dying grace and guilty conscious was screaming otherwise), they fell into a rhythm. Sam and Dean would go on hunts like they always do (Sam just for something to do and Dean to quell his ever pressing need to kill before he turned that First Blade on Sam or Cas), and Castiel would stay at the bunker, dealing with his faltering grace the best he could.

Most days, he would just lie in Dean's bed, falling into fits of restless sleep with Dean's scent in his nose and name on his lips. Some days, when the guilt and sorrow the room brought became too overwhelming, Castiel would force himself to leave, often choosing to wander through the bunker and become accustomed to its winding halls and hidden rooms. Of course, he would never last long before he would fall into a violent coughing fit and be forced to sit down for a few minutes to regain his strength, but at least he was making the effort to stay active for as long as he was capable of.

Hannah would visit sometimes, Castiel was delighted to admit. The first time she appeared (only a week after he had decided to stay at the bunker and rejoin the "Team Free Will" unit that was now falling to pieces), her smile dropped almost instantly into disapproving pursed lips upon smelling sulfur and iniquity, disgust palpable in her voice as she stated stiffly, "I see that you have yet to change your precious demon back into a human."

Castiel locked his jaw, pushing himself up from his slumped position on the couch and walking over to her, "All he needs is time, Hannah. Sam and I will convince him to let us change him back." When she narrowed her gaze, he added, "Eventually."

She eyed him with disbelief but didn't voice her skepticism, instead surveying the desolate area around them and saying casually, "Where is the demon and his brother now?"

Castiel would never get used to the word "demon" in description of Dean, always flinching at the name and biting back protests of denial despite the accuracy of the title. He grimaced and glanced away, ignoring her question and asking flatly, "What is wrong, Hannah? You would not come here without a reason."

"I came to see how you were doing," Hannah informed him, sincerity shining in her eyes as she hesitantly laid a hand on his shoulder and peered at his fading grace with her omniscient eyes, "It's getting worse. It won't be much longer until..." She looked up into his eyes and trailed off, raw pain and frustration in her gaze as she demanded curtly, "Please, why won't you let us help you? We'll figure something out, Castiel. Heaven—"

"Heaven is not as supreme and all-powerful as it used to be," Castiel reminded her gently, "And for me to take another angel's grace would only result in an innocent's life to be lost. I can't do that, Hannah, just as you couldn't allow anymore unnecessary deaths and convinced me to lock Metatron away for all eternity instead of ending his life."

She clenched her jaw and tore her gaze away, releasing her grip on his shoulder and taking a step back. In mere seconds, she changed from his friend to his business associate, saying in a professional, detached tone, "I hate to disturb you or your health any further, but Heaven has discovered more rogue angels. I wanted to go by myself to retrieve them to spare you any stress, but I'm not good at handling rebels." She let out an exasperated sigh, her hands clenching into tight fists at her sides, "I don't understand why they would pick humanity over their celestial home. But you do," She took a step forward, her eyes pleading, "It will take a day at the most. Please, Castiel. Heaven needs you."

Heaven always needs me, he thought bitterly but pushed it away before Hannah could detect it, smiling tightly at her and nodding in reluctant agreement. She was so young and out of her depth—so naive and idealistic, still holding tightly onto the ridiculous belief that Heaven was as divine and almighty as they forced you to believe. Castiel remembered what it was like to be in her shoes, many years ago when he was assigned to look after his charge that eventually shifted into being his cause of rebellion. She will learn one day, he thought to himself with both delight at another angel's choice of free will and dread for the inevitable consequences, hopefully by then she will have found her own Righteous Man to cling to when that happens.

Without a thought to write Sam and Dean a quick note in case they get back before he did, Castiel led Hannah to the car and drove up off.

When Castiel arrived back at the bunker, it was around midnight and the bunker was a tousled mess.

Furniture was destroyed and strung out throughout the rooms and hallways, leaving a clear path of wreckage that stopped just at the closed kitchen door. Speaking of the kitchen, Castiel thought, tentatively making his way towards it, which was thundering with nameless objects being broken and Sam's feeble shouts for someone—the destroyer, Castiel was guessing—to stop. Dean was his immediate worry, his angel blade slipping from his sleeve and into his readying hand.

"Dean?" The angel called out, hoping his voice would carry over the ruckus, "Sam?" Not even a moment after, Sam busted through the door and let out a loud sigh of relief when he caught sight of Castiel

"Cas, thank God." The youngest Winchester sighed out with a smile, though his eyes were still wide with terror. He turned towards the kitchen and yelled hesitantly, "Dean, stop. Cas is back."

Abruptly, all sounds of demolition ceased. Instead, the sound of heavy, angry footsteps took its place before Dean appeared right in front of Castiel's face, emotions of fury and betrayal and panic mixing effortlessly in his stony expression. Before Castiel could demand what was wrong, Dean grabbed the collar of his shirt and jerked him up in the air, demanding in a low, dangerous growl, "And where the fuck have you been?" Castiel tilted his head and stared confusedly into Dean's black eyes, his expression of puzzlement and agitation at the other's hostility his only response.

"Dean, cut it out." Sam said as he gripped his brother's shoulder tightly until Dean finally released Castiel. The angel, whose strength was already utterly drained in result of the heated battle he only barely survived with Hannah, almost fell to the ground without the support, but Dean caught him just before he hit the floor.

For a few tense, heart-pounding moments, the whole world bled away and all that was left was the two, Dean clutching Castiel hard enough to leave bruises and Castiel wrapping his hands around Dean's clenched fists and squeezing them with mild panic and reassurance. But then, without warning, the moment shattered as Dean lowered Cas to the floor and crossed his arms over his chest, still too angry and high-strung to switch his black eyes back to green.

"Look," Sam, ever the peacekeeper, said gently, coming to stand beside both of them and clasping their shoulders, "We're all a little emotional right now, so why don't we—" Finally, Castiel just couldn't take it anymore and pressed two fingers to Sam's forehead, peacefully knocking him out in an instant. Dean caught him before he could flop to the ground and set him down on to the tattered remains of the couch. The gesture was so terribly thoughtful and Dean-like that Castiel felt his narrowed gaze soften...

That is, before the demon turned back around and slammed Cas against the wall, ignoring the angel's groan of pain as he demanded, "Now answer the goddamn question, Castiel: Where. Were. You?"

"I was helping Hannah track down rogue angels to bring them back to Heaven," The angel answered gruffly, glaring bullets at Dean while trying not to shudder under his bruising touch, "It's what I do now, Dean. I need to help Heaven in any way I—"

"Bullshit!" The demon barked, "You're doing it for her, aren't you? She your lost cause now, Cas? Since I'm too gone to be saved, you think you can turn her into your hero?" Revulsion and hurt rippled through his expression like a stone casted into water as he added brokenly, "I can smell her all over you."

"We mended each other's wounds, Dean," Castiel growled, anger seizing his heart and loosening his tongue, "You're jealous of her for that? For helping me? Or would you much rather I die from blood loss than let her dare touch me? You know, maybe I should have let myself die," He shoved Dean, but because of his lack of his usual strength, Dean didn't budge (which only made Castiel even angrier), "At least then I could have died with dignity instead of like—"

"Shut up," Dean exclaimed through clenched teeth, seizing his face in his hands and forcing him to meet his wild-eyed gaze, "Just shut up, or I'll rip your fucking tongue out." For the first time, Castiel felt fear trickle down his spine, paralyzing his body and short-circuiting his mind. He tried to respond—to say what, Cas himself didn't even know—but all words died in his throat before they could reach his mouth.

Dean didn't give a damn about his shell-shocked silence, continuing in a gruff, desperate voice, "You always leave me, Cas. Every. Single. Time. No matter what I do for you or what happens between us, you leave and I'm left never knowing whether you'll come back or not. Fuck, most of the time, I believe that I'll never see you again." He sucked in a shaky breath, "Back then, I was weak and helpless, but now? Now I can do something about it. Now…I can keep you here forever." All terror flooded out of his system when Dean's switched back to green, and for a second, it was like Cas finally had him back, even for the briefest of moments.

"I never wanted to leave you, Dean. Not once," Castiel said quietly, "But as much as I wish otherwise, my duties don't end at just serving you and your brother. I have responsibilities in Heaven and my own needs. I...I can't just be your angel, Dean. I have to be my own."

Dean shook his head, "No, I won't let you. You're mine, don't you get that?"

Castiel felt himself harden in defense, the urge to argue about the possessive comment almost strong enough to win out over his common sense. But luckily, Cas knew how to play smart and pick his battles, so he forced the protests down his throat. It's only temporary, he assured himself, he'll snap out of this when he's human again. Just let him win this one battle.

Eventually, when the silence became too deafening, Castiel snapped out of his reverie and purposely lowered his gaze in feigned submission, rasping out tiredly, "I've always been yours, Dean. But these missions with Hannah—they make me feel stronger. Sometimes, along with you and Sam, they're the only thing that keep me going." It was a lie. All logic pointed to that, but graciously, Dean wasn't thinking logically at the moment.

"Promise you'll always come back," Dean pleaded tersely, grasping his chin and forcing his head upward to look at him, "Just promise, and I'll let you go on your stupid crusade."

Castiel cleared his throat, this time speaking the truth, "I promise."

Dean's shoulders sagged with relief and he took a few steps back to give Castiel room to breathe, "Good." He then looked over at Sam, and his eyes softened, and it was in these moments that Castiel let himself believe that his Dean was still in there somewhere.

"I'm going to lug him to his bed and clean up," Dean said casually, as if he didn't just have a mental breakdown, "You go wash up and wait in my room. I'll be there in an hour or so." It wasn't a suggestion, but Castiel was going to do that anyway, so he didn't challenge it. Instead he nodded and walked sluggishly to the shower, only stopping when he heard Dean say, "Cas?"

He turned, arching an eyebrow, "Yes, Dean?"

"I'll do it, you know," The demon said, biting his lip, "I'll—I'll slaughter a thousand dicks with wings if that means I can keep you forever." It was probably meant to be flattering, but all the statement did was churn his stomach.

But Castiel smiled weakly anyways, saying, "I know, Dean, but don't, okay? We'll find another way. Me, you, and Sam—we'll be together forever, one way or another." The words sounded forced and insincere in his own ears, but Dean smiled widely at him and nodded.

Under the hot sprays of the shower, Castiel tried to wash away the feeling that he was losing control of the situation along with the dirt and grime. It didn't work, but at least he tried.

Author's Note: Only a few more chapters left! Please remember to review, follow, or favorite.