The chime of a bell announced Castiel's entry with a muted excitement. He paused, glancing up at the tiny contraption suspended above the door, then over the mostly empty space. A sign at the hostess stand read "Please Seat Yourself" which, according to Dean, was a directive to proceed to one of the tables, and not to sit upon the floor in wait until the hostess's return. His gaze skated over the room before he selected the table he thought Dean might pick, sliding into the corner booth. Then, he waited in silence, his eyes lingering on the glass door.

After almost a minute, a woman in a uniform, blue dress approached his table, a notepad in hand. "Can I get you something?" She followed his gaze to the door, "Or are you waiting for someone first?"

Castiel looked over the woman and her bright, warm soul, before his eyes flicked up to hers, "Do you have coffee?"

She snorted a chuckle, "'Course."

"I'll take one black, please." He'd seen the Winchesters order it plenty, and it was something he was certain he had the appropriate funds to afford.

"Anything else?" At the shake of his head, the woman nodded and pocketed her notebook, "One black coffee, coming right up."

Castiel's careful watch over the door resumed, though he sensed the nearing presence before he saw it.

The bell rang again as a woman stepped through the door, her blonde hair knitted tight in a ponytail, her eyes thinned and wary as they surveyed the space. If Castiel's sight extended only to the physical, he wouldn't recognize her, even as she locked gazes with him. Yet, the invisible radiant glow of holiness, the unmistakable weaving and coil of celestial wavelengths, the crackle of divine power—they were unmistakable.

She crossed the distance without hesitation, sliding into the booth across from Castiel. For a brief moment, the two silently regarded each other, before the latter cleared his throat.

"It's good to see you, Zophiel." He offered her a simple smile, "You look well."

She frowned, tilting her head, "I wish I could say the same."

Castiel dropped his gaze at the blunt, but apt assessment. If the Winchesters could observe enough to spark their concern, despite the limitations of their human eyes, an angel would have to be blind not to notice the fading of his very essence.

"Your choice of location is… curious," Zophiel remarked, eyes flicking notably to the waitress approaching with a coffee pot.

The two angels remained silent as the waitress poured Castiel's cup of coffee; the woman glanced over Zophiel, forcing a smile in response to the emotionless stare, "Welcome to Jennie's Diner—can I get you anything? Coffee?"

The angel shook her head, "No."

Castiel offered the waitress a smile, attempting not the kind Dean donned when he was apparently attempting to score the woman's number, but the kind Sam usually offered when the woman didn't seem to know how to respond to something Dean or Castiel said. "Thank you."

She nodded, inviting, "Let me know if you need anything else," before starting toward another table.

Castiel brought the mug to his lips, sipping the warm drink. When it hit his tongue, a wisp of disappointment sparked in his chest. In his brief stint with humanity, he'd experienced a sensation he'd previously couldn't even conceive. It wasn't quite mere taste, but… perhaps the capacity for enjoyment of it. The tiny pleasures that defined the human existence, something the angels didn't share and, frankly, couldn't understand without experiencing it themselves. Now, with grace empowering his every atom once more, he could distinguish every component of the drink as it fell upon his tongue, when, as a human, the best he could hope for in such a regard was the hazy guess of an unrefined palate. But, somehow… he didn't find this better.

Zophiel stared at him as he set the mug on the table, eventually commenting, "You've spent too much time with the Winchesters."

Castiel exhaled, ignoring her remark, "How are you, Zophiel?"

She shook her head, her lips quirking in a mild smile, "There's no need for pleasantries. We both know that's not why you summoned me."

He dropped his gaze, guilt twinging his chest, "I'm sorry. Things have been… difficult, lately."

She waved a hand in dismissal, as though the offense was already forgotten, "The Mark. So I presume you were successful in curing the Winchester?"

Castiel nodded, "The Rite of Sanctified Blood cured Dean of his demonic nature, but… the Mark remains intact."

Her expression read no surprise. "As expected."

"Have you found anything?" Castiel prompted hesitantly, though anticipating her reply from the lack of forthcoming information.

She offered no padding or inflection of wary concern, stating bluntly, "Heaven's archives contain no mention of a cure for the Mark." Castiel's face fell, and she looked over him, "Castiel… perhaps Father did not make the curse as something to be cured."

"I can't believe that." Castiel refuted. Dean would not be cursed with the Mark for eternity. He couldn't be.

The angel started carefully, watching him closely as she spoke, "Brother, you and the Winchesters have searched for a cure for months, now, and you remain no closer to one than the moment the Mark first branded his arm." She paused, "It may be time to consider alternative measures."

Castiel frowned, brow furrowing, "Alternative measures?"

"If the Mark is indeed incurable, it is inevitable that Dean Winchester will succumb to its influence. In a matter of time, he will likely die and be reborn as a demon once more, like Cain. And when that occurs, when he loses control, he will kill thousands, Castiel."

"Dean is strong," Castiel asserted, "He will not succumb to the Mark soon." Cain had endured centuries—perhaps he'd overcome its call altogether. Dean was among the most capable humans Castiel had known. Surely he could learn to do the same.

"But he will succumb." Zophiel's face bordered almost on sympathy—perhaps Castiel wasn't the only one passing time with the humans. "I understand you are fond of him, and I don't doubt his strength, but the Mark will not be subdued forever. And when it claims him, it will likely be too late."

"What would you suggest, then?" Castiel asked, voice terse, "It may not even be possible to kill him, not while he bears the Mark."

Her hesitation forewarned the nature of her words, "If we ascertain that killing him is truly impossible… it might be sufficient to merely… incapacitate him. To deposit him in the ocean, or to solidify him in stone, perhaps."

Castiel's expression darkened, repulsed at the thought of Dean spending eternity at the bottom of the sea or buried in cement, "That would be torture."

She held his gaze unflinching, "The alternative may be mass genocide."

"It's not an option," Castiel refused, shaking his head. He couldn't think to suggest such a thing to the Winchesters. Killing the thing that Dean had become was one thing—painful, to be sure, but easier when Castiel reminded himself that it would merely free his soul to ascend to the heavens, where it would rest in well-earned peace. But condemning him to suffer in lonely agony for all eternity? Castiel thought the churning of his gut might cause him to spew across the table the bile that had been growing in his stomach in an increasingly unpleasant ache.

Frustration wrinkled the corners of his sister's face, "You're allowing your attachments to hinder your reason, brother. I fought beside you because I shared your belief that humans are worthy of life. You may be risking thousands of innocent human lives with your reluctance to act—not to mention the lives of your brethren to whom you will leave the task of restraining the Winchester in the midst of his brutal massacre."

Castiel was silent for a long moment, finally meeting her eyes, "If it comes to it, I have faith that Dean will do what must be done." Before Zophiel could remark, he added firmly, "But it hasn't come to that. And it won't."

She sighed quietly, "It's dangerous to leave this unaddressed."

"We will not condemn Dean to an eternity of suffering while there may still be a way to remove the Mark." Castiel's tone bespoke finality. "Have you managed to locate Cain?"

Zophiel's gaze dropped to the table, and she released a careful breath before glancing back toward Castiel, "We've detected signs of powerful demonic movement in Pennsylvania. He's… elusive, but if I had to guess, he's there."

Tentative hope sparked in Castiel's chest. Cain had been the one to curse Dean with the Mark, rendering him one of their best chances at finding a cure. And if they couldn't… well, Cain had gone decades without succumbing to the Mark. At the very least, he owed Dean an explanation of how he managed to resist—a debt that Castiel would ensure the old demon paid, if the angel could help it.

Reading his expression, Zophiel warned, "Cain is not to be underestimated, Castiel. He's one of the oldest demons—the captain of the Knights of Hell. Restraining him, let alone convincing him to help your Winchester, isn't going to be nearly as easy as neutralizing your freshly turned demon friend."

"I know," Castiel's voice was low, solemn. Cain was powerful, and he'd had centuries to hone his grisly talent. "I won't ask you, or any other angels, to risk yourselves. You have already sacrificed much on my behalf. I merely ask that… if you're willing… you keep me apprised on his whereabouts."

She cocked an eyebrow, "And… what? You're strong, Castiel, but even at full strength…" The angel trailed off, her expression wrinkling in a rare display of genuine concern. "Cain is dangerous. Even with the Winchesters' help, in your state…" She shook her head, "It would be foolish to try."

Castiel smiled softly, "I appreciate your concern, sister. But if there's even a chance he could help save Dean… I have to take it."

Zophiel exhaled with another, almost disbelieving shake of her head, "Your recklessness rivals that of the Winchesters." Castiel's lips curled faintly at the comparison. "Very well. I will speak with our brethren to try to ascertain Cain's exact location and to monitor his behavior. Though if we see an opportunity to detain him, we'll take it."

Castiel frowned, "You shouldn't risk yourself. I don't want to lose any more of our brothers and sisters."

"You insult me," she upturned her chin in mock offense, her eyes betraying the tone of the words before she sobered to assure, "We'll exercise caution. And if any of our number do fall, they will fall knowing they gave their life working to spare the world from the destruction of the Mark of Cain."

Castiel clenched his jaw. He didn't want his brethren to sacrifice themselves—he already bore enough angelic blood on his hands. None of them should die on a mere chance to save Dean—not while Castiel still drew breath.

Evidently noticing his hesitation, Zophiel continued, "If our brothers and sisters wish to help, it will be of their own free will. Something you taught us." After a moment of contemplation, she added, "Your heart is usually in the right place, Castiel. It's true that your… mistakes have had grave consequences in the past—" Castiel dropped his head a degree in shame, guilt prickling his skin. "—but you have done your best to rectify them." Her tone was level—not cruel, but blunt in honesty. "I merely pray that this occasion does not share in the prior misfortunes of some of your decisions."

Silently, Castiel prayed the same.

After several seconds of unmoving silence, the angel leaned back, glancing over the near-empty diner absently, "It's somewhat ironic, don't you think?"

Castiel's brow furrowed, "What?"

"Dean Winchester—once heralded as our champion among men. The very sword of Michael himself. The instrument meant to end the world's suffering and usher in paradise. That he's the one to bear this curse, to threaten untold destruction upon the world he was supposed to save." She shrugged with a wry smile, "I thought it was supposed to be the other one—the abomination—that was supposed to raze this planet."

Castiel's scowl deepened, his heartrate accelerating a few ticks. A cough wrought its way from his throat, earning him a glance from the corner of her vision. When he finally subdued the scratch of his throat, he ground out carefully, "Sam Winchester has more than atoned for his role in the Apocalypse. He overcame Lucifer and spared the world our brothers' wrath—something none of us were able to do—and he suffered greatly for it."

Zophiel's expression grew serious, somber, and she nodded, "I know." She offered a simple, sideways smile, "He's redeemed himself far more than I ever expected, for one with demon blood in his veins."

Castiel shifted in the booth, gaze flicking over the diner before returning to her. Perhaps it would be wiser to merely agree, given the circumstances, but Castiel couldn't let the statement lie. Maybe the disquiet spawned from an urge to defend his friend from aspersions, or maybe it was a mere need to remind himself of his friend's innocence in the unjust fate into which he'd been cast.

He spoke quietly, carefully, "The demon blood infection wasn't Sam's fault. He was an infant when the demon prince cursed him—before it killed his mother above his head." If anything, it was the angels' fault for allowing it to happen. For he knew, at the very least, Michael, ever watchful of his perfect vessel, had seen, had known, and done nothing.

The angel acquiesced with a contemplative nod, then shrugged, "I suppose it's not a lion's fault that it must kill to survive." At Castiel's discomforted silence, she added, as though in appeasement, "It is good that he abandoned his… infernal habit, though. Perhaps you're right; he's come a long way, since then."

Still silent, Castiel only forced himself a nod, this time restraining his tongue. He swallowed hard, praying that she wouldn't read the truth behind his eyes. He wasn't certain what the angels would do, if they learned of Sam's relapse, but he was certain they wouldn't offer support in his recovery, nor would they understand it wasn't his fault. And if they learned Castiel was supplying the Winchester with the accursed blood, that some waited in his car even now, just a few yards away? Even the few that had remained loyal to him, despite everything, might just slay him on the spot.

"Speaking of the abomination," Zophiel caught the irritated flick of Castiel's eyes, and paused as though in apology for her phrasing, "There might be someone else who knows how to remove the Mark."

Castiel tilted his head, frowning warily, "Who?"

"The one who branded Cain's arm with it in the first place."

Castiel's eyes narrowed into slits, his voice darkening, "No."

She inclined her head in acceptance, apparently willing to drop the suggestion at Castiel's instant verdict.

Yet, as silence ticked past a minute, Castiel mulled the thought, finally voicing, "We can't risk his release again."

"I agree," Zophiel nodded, elaborating slowly, "But it could be possible to communicate with him without opening the Cage." Her azure eyes searched his, cautious, "You know how strong a bond between an angel and their vessel can be."

It was true—an angel and their vessel were strung together with an invisible tie, linked with the grace that lingered in the body from the possession. With a few lines of Enochian, it was theoretically possible to reach the angel through the vessel—something he and Dean had done many years ago, when trying to lure Raphael back into his comatose vessel in the early days of the Apocalypse. Such a bond was assuredly all the more powerful between an archangel and their perfect vessel—but that was a fact Sam need never know. Even though threads of Lucifer's weaved tight into the scars of his tormented soul, hopelessly intertwined and blatantly visible to any angel who dared to look.

As uneasy dread crept along his veins, Castiel shook his head, "The Cage's warding is strong. Even Lucifer can't penetrate it." Though even as he spoke, he knew the archangel had—he'd contacted Azazel to impart his plan for Sam's destiny, eleven years before the Winchester had ever even drawn a breath.

"You may be right," she raised her shoulders, "There's no assurance it would succeed, or that Lucifer would even deign to help. I merely thought it could prove less dangerous than inaction."

As long as they didn't open the Cage, it might be less dangerous for the world, but the cost of such an interaction to Sam? In his current state… Castiel couldn't imagine.

He again wrung his head, this time in finality, "No."

"Very well," she accepted, studying him. "I didn't mean to offend—I only mentioned it as a potential solution to spare your Winchester, even if it's far from ideal."

Castiel dipped his head a degree in acknowledgment, holding a fist up to his mouth in an attempt to restrain a further hack that tormented his throat.

The angel's expression twisted in something not far from concern, then she glanced over the diner. "I suppose I should take my leave. But, before I depart," she slid something from her sleeve beneath the table, and felt the distinct ring of divinity moments before she raised her arm and proffered it toward Castiel. On her wrist, bright, holy grace curled in radiant tendrils from a slender incision in her skin. His eyes flicked to hers, and she supplemented, "You need it, Castiel."

He pushed her hand downward, away, "Zophiel, I can't take your grace."

"I'm not offering all of it," her lips curled faintly for a moment, "It won't serve as a permanent solution, but it might spare you a few more days, if not weeks. I would be saddened at your demise, brother. Take it."

Castiel stared at her. It was tempting, undeniably. To ease the pain that gradually crept upon his weakening body, to empower him with the strength and buy him a little more time to ensure the Winchesters' safety. A small amount would only weaken Zophiel temporarily.

And yet… he couldn't.

He had taken so much from his brethren, more than once. He couldn't take one more thing, even if offered freely. He simply didn't deserve it.

He shook his head, "I can't." She would need it, if she was to tail Cain. And though her grace would slowly recharge, it wasn't a true solution, anyway—he would burn through her grace far quicker than she could spare it.

She waited several moments, perhaps allowing him a chance to change his mind or in an attempt to deduce why he refused, before she sealed the thin cut with a brush of her thumb. "If you're certain."

He smiled softly, "Thank you, sister." He paused, uncertainty wringing hesitation, before he raised his gaze, "…Zophiel?"

The angel tilted her head and raised an eyebrow in invitation to proceed.

"If… anything were to happen to me…"

"I'll keep an eye on the Winchesters," she replied before he could summon the courage to finish the undeserving request. Her expression read sincerity, "I cannot avow to their safety, but if you fall, I will endeavor to guard them as you have, in your memory, for as long as they remain soldiers of the light."

He dropped his gaze in a poor attempt to veil the emotion clawing at his throat—still a strange sensation. He didn't have the right to impose such a request upon his sister, and he knew she shared no particular love or devotion to the Winchesters. But… it offered him some comfort, nonetheless.

Zophiel stood, saluting him with a fist to her chest, "I hope you find a cure, brother. I will update you with Cain's whereabouts when I know more."

With that, she disappeared through the glass doors without a single glance backwards. After a few minutes, and after tossing a few bills onto the table, Castiel followed her lead outside, releasing a tired exhale as he approached his car. He swung the door closed behind him, reaching over the seat to check the cooler, ensuring the bottle of demon blood was still safely secured inside, before he fished his cellphone from his coat pocket.

He squinted at the small letters, then punched out a message to Sam. I may have a lead on Cain's whereabouts. – Castiel.

After staring at the screen for several minutes, he sat his phone on the seat beside him and started the car. The Winchesters might be preoccupied cleaning up after their hunt. He prayed all had gone well, for he couldn't help but think neither of them should be hunting in their state, despite both their insistences to the contrary.

Twenty-seven minutes later, his phone began to buzz, shaking across the seat with the intensity of its vibrations. Castiel fumbled to grasp it even as he pulled off the road, shifting to park.

"Hello?"

"Hey, Cas," Sam's tired voice crackled through the speaker.

"Sam. Is Dean with you?"

"We stopped for gas," Sam replied, words clipped. "He'll be inside for a few minutes. What've you got?"

"I spoke with an angel that's been monitoring Cain's movements. She's tracked him to Pennsylvania, and she'll try to keep an eye on him until it's safe to act." He paused, measuring the hope in his words, "If we can find him, we may be able to convince him to remove the Mark from Dean."

"I thought you were supposed to be resting up," Sam noted with a faint, quiet edge of amusement in his otherwise exhausted tone.

Castiel shifted guilty, "…apologies."

"So this angel, you trust her?"

"She fought with me against Raphael and Metatron. She's one of heaven's finest soldiers." And one of the few to respond to Castiel's calls, one of the few to still trust his good intentions, even after the horrors he'd wrought against heaven.

"Okay… sounds like good work, Cas."

The angel glanced at the time, then toward the dark sky, "How about you two—how was the hunt?"

Sam was silent for a long moment, escalating Castiel's worry. When he did speak, every word was heavy, "We, uh… we ran into a little trouble."

"Are you both okay?"

"We're fine," he heard Sam exhale through the speaker, then the scuff of his feet against the asphalt, "We found a few demons following us. More hex bags, like you said. Crowley's had them watching us, apparently."

Alarm and concern tightened Castiel's voice, "Are you still…"

"On schedule?" Sam finished, sparing him the words. His every syllable was weighted in fatigue. "Yeah, I… I didn't take any."

Relief immediately eased the tension from Castiel's grip, "That's good news. I'm glad to hear it, Sam."

"Yeah," Sam finally spoke after several seconds of silence, though his tone was dry, devoid of conviction as he echoed hollowly, "Good news."

Castiel frowned. Sam's tone was… confusing. Castiel didn't believe him to be lying, but Sam spoke with such defeat as though he had relapsed instead of resisted. "Is everything alright, Sam?"

"Yeah, Cas, I, uh…" he answered readily, then then hesitated and released a heavy sigh, "Honestly… I dunno."

Before the angel could determine an appropriate reply, Sam spoke again, his words curt, hasty, "Gotta go."

The call cut out, and Castiel dropped the phone onto the seat, his exhale turning into a shallow cough.

Sam sounded exhausted, but that was understandable, given everything. He was dealing with a lot—too much. Both Winchesters were. The angel shook his head. It wasn't fair that they were to carry such heavy burdens yet again. They had already sacrificed enough.

He shifted the car into drive, pulling back onto the road, and silently prayed that Cain would be readily forthcoming with a cure for Dean. For the old demon's own sake.