Castiel reluctantly let go of Dean, though his wings were puffed up protectively around the human still. He realized that Dean could probably see this, but he didn't say anything. Once upon a time, Cas was worried that Dean might freak out if he saw the angel's giant wings fully (well, almost fully) corporeal. But, much to Cas's surprise and relief, the human seemed rather awed by them.

"I wish you could feel them," Cas said quietly, looking away from Dean's gaze.

Dean gave him a confused look, clearly not knowing what he was referring to.

"My wings," Cas clarified. "I'm happy you can see them now, but..." he trailed off and frowned at the ground.

"They're beautiful," Dean said, giving the angel a shy smile. "I, um, I was wondering why they're black, though. Is it because you fell from Heaven, or...?"

Oh. That.

It's not that Cas didn't want Dean to know, he just wasn't quite sure how to say it without getting massively embarrassed.

"Sort of," the angel answered, daring to look back up at the human's emerald eyes. "They started out white, as all angel wings do. Over time, though, after I... rescued you from Hell and started helping you and your brother, they changed. They darkened from white to gray and eventually to black. Though, they were never fully black until now. After I got back from the Empty, I mean. I guess... I guess it would've been hard to tell anyway during the time when they got partially broken, but I think they were a very dark shade of gray before that happened."

Dean took this new information in with wide eyes and a slightly agape mouth.

"Do you miss the white wings?" the human eventually managed to ask.

Cas shrugged, "Not really. I think these make me more unique."

"Trust me, Cas, you're not like any other angel I've met," Dean said, only half-joking.

Cas smiled, "You're not like any other human I've met. Not even Sam."

"So I've been told," Dean mused, sounding a little tired.

"Can I... read you?" Cas asked, not knowing if he was breaching some kind of privacy. "Like, um, your soul, I mean. I felt it when I pulled you out of Hell and again when you pulled me out of the Empty, but I'd like to read it when one of us isn't in immediate danger... if you... wouldn't mind, that is."

Dean looked a little uncertain. "You mean the whole hand through the chest thing? 'Cause that shit didn't look pleasant."

"Oh, no. Not that. With our bond, I should only need to touch you to feel it. I... I've thought about doing it recently, but I wanted your permission first," Cas explained, feeling his face flush a little.

"Sure, I guess," Dean said, though he looked a little uncomfortable. "As long as it won't hurt."

"It won't," the angel assured him.

Cas took hold of Dean's hand—the one that wasn't holding the poem—and looked at the human through the eyes of his true form. All human souls were complex, made from energy that was nearly infinite. There weren't proper words in any language to describe their appearance. The easiest the angel could think of would be comparing them to stars. Some were dimmer than others, some had hues of blue or purple or red or gold. In that way, Cas supposed they were a bit similar to an angel's true form, at least from a pure energy perspective.

What a human soul actually looked like was... Well, the raw energy was tightly condensed in the general chest area. Thousands of tiny tendrils of light spread out from there, extending past a human's physical body. Since angels—in their true form—saw a human's soul rather than their physical body, it could be a bit difficult to differentiate between people. Each soul was unique, yes, but ultimately they were all tightly packed balls of energy.

When Cas had first seen Dean's soul in Hell, he was momentarily stunned by the intensity of it. And by its color. It was pure white light, illuminating the otherwise inky blackness surrounding it. Perhaps there were other humans with a soul colored the same as Dean's, but in all his years of existence Castiel had never met one.

Once Cas was formally introduced to the human back on Earth, he had to remind himself to look at Dean's physical appearance rather than his soul. It was difficult at first, but over time he got used to it. He hadn't looked at it directly for several years now, so he wondered if it would be the same or if all the trauma Dean had faced since then would have changed it at all.

Now, of course, there was more to reading a human's soul than just looking at it. If that's all Cas wanted to do he would've done it without asking Dean beforehand. Reading a soul was more than examining its color or energy level. It was an examination of a human's true nature, in a way.

Knowing how intimate of a gesture this was, Cas wanted expressed permission beforehand.

Now, with his hand on Dean's and his eyes on the human, Cas could properly look at Dean's soul.

It was still a blinding white light, with tendrils extending from Dean outward like a blossoming flower. The energy of the human's soul also seemed to be reaching out to Cas specifically, perhaps a residual effect of their bond.

The angel shut his human eyes and opened the many eyes of his real body to more effectively read Dean's soul. He'd read the human's soul while he was trapped in Hell and saw much pain and torment but also sparks of hope and even love.

Of course, at the time Cas didn't really understand humans very well, so he didn't fully grasp the depths of Dean's capacity for love until much, much later.

Now, Cas read empathy and compassion and affection and love making up the major components of Dean's soul. Though, he realized a beat later, that could be in direct relation to himself. If Dean's soul was already reaching out to him instinctively, Cas was likely reading how Dean felt specifically about him on a very subconscious, almost spiritual level.

It was both extremely flattering and overwhelming for the angel.

"Cas, you okay?" Dean questioned distantly.

Cas was more than okay. He knew the human loved him, since Dean had told him as much on multiple occasions, but this was different. It was almost too much for the angel to process.

He felt Dean's hand drift from his own and then felt both of Dean's hands on his shoulders, gently shaking him.

"Cas? What's goin' on, buddy? You're zonin' out and it's scaring me. What's happenin' in that angelic brain of yours?"

Cas couldn't find the right words to answer that question with. At least, not in any human way Dean would understand.

Emotions were still something Cas was learning to handle, so this experience was making all of his already unstable-on-a-good-day emotions completely fritz out. He was elated, ecstatic. He felt such an extreme surge of adoration for Dean that all he wanted to do was pull the human close to him and never let go.

What ended up happening was slightly different.

Cas finally opened his eyes, finding Dean only inches from his face now and looking extremely concerned. The human's eyes widened suddenly and he glanced over at the angel's wings, which were fluffed up significantly more than normal. It was completely involuntary, Cas's overflow of human emotions leaking into his true form and causing him to puff up, not unlike a bird.

He supposed the subconscious intent was to show off a bit, though angels were never supposed to be prideful.

"You're... happy?" Dean guessed helplessly.

Cas managed a tight nod, still not able to get any words out.

"Your eyes are... glowing. Should I... be concerned?"

"No," Cas said quickly, forcing himself to snap back to reality. "Sorry, I guess I got a bit carried away."

He tried to reign his grace back in and keep his true form under control. The last thing he ever wanted was to accidentally hurt Dean with it.

"It's okay," Dean said, though he still looked shaken by the incident. "So um... What does my soul look like?"

"It's as glorious as the day I first saw it. Thank you for allowing me to do this, Dean. Your soul is such a precious thing and I will always protect it."

Dean, as per usual, did not know how to respond to such a statement. That is, until he said, "Can I... see you, Cas? Like, the real you? The 'multidimensional celestial wavelength of intent' 'tall as the Chrysler building' version of you?"

He asked the question very timidly, as if he was afraid of the answer.

"As you know, the true forms of angels aren't meant for human eyes. Though, perhaps there is a different way I could show you."

Dean gave him a questioning look, confused.

"In a dream," Cas explained. "I could show you my true form in a dream."

Dean was still staring at Cas's floofed-up wings as the angel guided him to his room in the bunker. More than ever he wished he could touch the soft-looking feathers.

"Maybe now isn't the time for this," he found himself saying. "You should probably go back to the warehouse to keep an eye on those angels."

"This won't take long," Cas said, stopping next to Dean's bed and gesturing for him to sit down on it.

Dean obliged and raised an eyebrow skeptically. "Okay, um, what now?"

Cas reached out a hand and was about to place two fingertips on the human's forehead. Dean stopped him, saying, "Uh-uh. I don't like it when you do that. It's not nice to knock people unconscious, Cas."

"It'll take too long for you to fall asleep on your own, though," the angel complained. "This is much easier."

"Let's just do this another time," Dean insisted. "I need sleep—actual sleep—anyways, and you need to keep an eye on those angels until morning."

"Fine," Cas relented, looking a bit disappointed.

He dropped his hand to his side and his wings also drooped slightly before he tucked them behind his back again.

"There'll be other times," Dean said, trying to cheer him up.

"Yeah, I guess so."

Seeing that the angel was still a bit dejected, Dean stood up and pulled him in for a kiss. His wings fanned out again, perhaps involuntarily, and wrapped around Dean's shoulders.

"Dean..." Cas gasped out when they pulled back apart for a moment.

"An apology for the raincheck," the human shrugged with a little smirk.

Cas's eyes were glowing slightly again, as if the kiss had somehow sent an electrical charge through his body. Rather than responding, he grabbed Dean by his flannel and pressed quite a firm kiss against his lips. Cocooned by Cas's midnight-colored wings and entirely captivated by the angel's lips against his own, Dean temporarily forgot about the mysterious ancient box still sitting out in the war room and the two captive angels Cas was currently supposed to be watching.

Cas started sucking along Dean's jawline before the human got a chance to deepen the initial kiss. Dean wrapped his arms around the angel, letting out a small gasp of surprise when he felt... something protruding from Cas's shoulder blades. Apparently the angel could feel the point of contact as well, because he let out a soft groan against Dean's skin.

"I can feel... your wings..." the human managed.

He could feel the base of them, at least. A solid attachment from Cas's human body to the distinctly not-human part of him. Dean supposed he shouldn't be too surprised to feel the structure of bones, since it would make logical sense for the angel's wings to be supported by some material similar to human—or perhaps bird?—bones.

"That's..." Cas trailed off and pulled back from the human to give him a slightly dazed look. "How? You shouldn't be able to do that."

Dean didn't know how he was able to feel the base of Cas's wings, but at the moment he didn't really care. He wordlessly pulled the angel's trench-coat off, along with the suit jacket he was wearing underneath. Cas didn't object, though he gave Dean a quizzical look. Dean smirked a little and untucked Cas's white button-up from his trousers so he could snake his hands up the angel's back. Cas shivered at the human's touch and leaned into Dean reflexively, his blue eyes fluttering closed momentarily. Dean's fingertips found the bone attachments that lead to Cas's multidimensional wings and he ran his hands along the peculiar structure that lay beneath a thin layer of skin.

"That feels… I've never had anyone…" Cas trailed off, a little breathless. "I wish you could feel my wings," he said, repeating his statement from earlier.

"Me too," Dean agreed.

"I want you to feel them," Cas said more forcefully.

He opened his eyes again and fixed Dean with that icy-blue angelic stare of his. It was unnerving in a way, like he was almost looking through Dean, straight to his soul. Perhaps he was. Cas retracted his wings from around Dean and let them span out behind him to their full length. They stretched across the human's bedroom and even then seemed a little squished. In height they were a few inches taller than Cas at their tallest peaks, probably Sam's height. Dean was once again made speechless by their ethereal beauty.

Cas gently moved Dean's hands from behind the angel's back to briefly lace them in his own, before guiding one of them to one of his wings. Dean let out a gasp of surprise when he felt his fingers touch the inky black feathers. They were silky smooth.

"It takes quite a lot of energy for me to keep them corporeal for you in this plane of existence, but it is manageable for short periods of time," Cas explained softly.

"They're so soft!" Dean blurted out, then flushed, feeling like an idiot for saying his thoughts out loud.

"Yes," Cas replied, chuckling a little. "I'm happy you… like them."

"Of course I do," Dean said, grinning. "They're freaking awesome, man! You're such a badass."

"Does it bother you that I'm not human, though?" Cas asked seriously, his expression falling. "I mean, are you sure the wings don't bother you?"

"I think they're amazing, Cas," Dean said honestly. "And I don't give a shit that you're not human. You know that's never mattered to me."

Cas smiled and then released Dean's hand. "I wish I could keep them in this state for longer, but it's very taxing."

"It's all right. I'm sure there will be other times for more… exploration."

Dean hadn't meant for his words to sound suggestive in any way, but nonetheless the angel blushed slightly and replied, "Yes, Dean, I'm sure we will definitely be exploring each other much more in the future."

Cas tucked his wings back once more and put his suit jacket and trench-coat back on before announcing that he should probably get back to the warehouse. Dean agreed and kissed the angel again before saying goodnight. He fell asleep thinking of Cas's wings and how great they'd feel wrapped around him in bed.