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The first lesson (angel wings)
Castiel had been twitchy and acting odd all day, and Dean was suspicious about him keeping secrets from him again. When Cas wandered into the library where he and Sam sat doing research and moved along the walls restlessly, Dean lost his patience.
“Dude, what’s wrong with you? You’ve been all jumpy and avoided us for two days,” Dean asked. Cas looked at them startled and swallowed loudly. Dean gave Sam a pointed look and Sam shrugged.
“I’m having a little bit of a… problem. Nothing that should concern you,” Cas answered, avoiding Dean’s gaze.
“What kind of problem?” Sam asked.
“You cannot do anything about it,” Cas avoided the question.
“Out with it,” Dean said. “I want to know even if I can’t do anything to help.”
For a few seconds Cas seemed to be deep in thought until he sighed deeply.
“Alright,” he agreed. “My wings are feeling itchy. Usually I can’t even feel them on this plane of existence, but now I have increasingly felt them bothering me.”
“Wait, your actual angel wings?” Dean frowned.
“Yes, Dean, my actual angel wings that you cannot see, unless I let you,” Cas said. Dean resisted the urge to ask to see them right then, because he wanted to get into the main issue.
“So why would an angel’s wings itch all of a sudden?” Dean asked and gave Sam a questioning look. “Is there even any lore about that kind of thing?”
Now Cas looked awkward and avoided Dean’s gaze again.
“What aren’t you saying, Cas?” Dean pressed, seeing Cas’ expression. “You know what it’s about?”
“I suspect they need to be groomed,” Cas said. “Grooming is an act where another angel takes care of the feathers, cleans the wings of excessive feathers, and smooths them with wing oil.”
“Well, does it have to be another angel? Why don’t you ask someone else to do it? If we can see your wings if you let us, then one of us should be able to…” Dean said, practically volunteering for the job. Yeah okay, he was now interested to see Cas’ wings and find out if they were soft, sue him.
“Dean, you need to understand that angel wings are not used only for flying. It’s an intimate act where an angel must put themselves in a vulnerable position, and it requires absolute trust,” Cas said in a strict, forceful voice that made shudders go through Dean’s body. “The wings are also an incredibly erogenous zone and touching them is often foreplay to mating.”
The room fell silent.
“Oh,” Dean let out an awkward sound. Sam was glancing between them at a quick pace.
“Thank you for the offer, but I will excuse you for not knowing the implications,” Cas said. “As I have told you, I will manage.”
“Yeah, okay,” Dean said, feeling slightly disappointed for some reason. “Thanks for telling us. Good talk.”
After a few awkward minutes Cas sat at the table too and began to help them with the research.
The second lesson (angel mating)
“So,” Dean sat across from Cas in the kitchen with a coffee mug in hand, feeling glad that Sam wasn’t in the room this time. “You found any solution to your, uh, wing problem?”
“No, not yet,” Cas answered. “I managed to spread some oil on them, so they will keep for now.”
“That’s good,” Dean said, sipping his coffee and keeping his eyes on Cas. “Although why do I get the feeling you’re still not telling me everything?”
“Dean,” Cas sighed. “If you really need to know, the itching is most likely related to the angel mating season starting.”
“The what now?” Dean asked, eyes widening.
“Angel mating season. The number of angels has been greatly diminished by the battles and other events in the last couple of years, a situation which often triggers a need to mate and replenish the numbers in remaining angels,” Cas said.
“So you’re… horny?” Dean confirmed.
“In a way. However, I’m not human with human instincts, so we could say I’m angel horny. It’s a metaphysical need to join together and reproduce. Not only a biological urge, but an all-encompassing need to join with a suitable mate, both bodily and spiritually,” Cas explained seriously, looking Dean in the eye. Dean knew he was likely blushing bright red, but he couldn’t turn his gaze away.
“Uh, right,” he said, his need to join Cas in all those ways overwhelming him. Now he was really glad that Sam wasn’t in the room. Although Dean could hide his excitement from Cas, Sam would see through him in a second and say something about it.
“There are not many angels left, Dean. Definitely not any who would be willing to mate with me even if…” Cas cut himself short. “Not mating won’t kill me. It will only be an uncomfortable couple of days after the mating season properly starts. That is if the mating season ever properly starts. It’s only my own supposition, as I can’t ask any other angels about it.”
Dean nodded.
“Just ask if you need anything. If I can do anything,” Dean said and took another sip of coffee to distract himself. Cas gave him a long look.
“I will keep the offer in mind.”
The third lesson (angel gender)
“I have been thinking that maybe I should go away for a few weeks until the mating season passes,” Cas told Dean from his bedroom door. Dean had been listening to music and reading a book when Cas interrupted him.
“Cas, no. Won’t the season or whatever make you vulnerable to attacks? You’ll be safer here,” Dean asked. Cas stepped into the room and sat down.
“I would rather risk it than let you and Sam see me in the middle of it. As I remember it, I can get very, uh, intense during the season,” Cas explained.
“What does that mean?” Dean asked, trying to sound casual. Cas closed his eyes and breathed deeply.
“Do you know anything about angel genders?” Cas asked in return. Dean shook his head.
“Not like human ones, I expect?” he said dryly.
“Indeed not. For humans gender is not a biological prognosis, but more of a vague sign of the statistically more likely characteristics the individual may end up having. Angels, however, can be grouped into three distinct groups, and it’s tied to our essence and leads our mating habits,” Cas said. “I’m an alpha angel, which means my urge is to dominate the mating. I can also affect more submissive angels with my voice if I choose to. I’m not certain it will influence humans, but I would rather not risk unknowingly affecting you or Sam when my instincts are strong.”
All the talk of dominating and submission was giving Dean some very interesting thoughts, although he had no intention of saying aloud any of the things he was thinking. It would only make Cas think he was already fucking with Dean’s head and leave. Dean didn’t want Cas to be out there, alone, during the probably pretty intense and uncomfortable period.
“Are you going to be, uh, a physical threat to anyone?” Dean asked.
“I wouldn’t force anyone to mate with me if that is what you’re asking. Even in this case angels need explicit consent to enter the process,” Cas said. Dean nodded.
“So to summarize, you’re not a real threat to us, except that you could have some weirdly Dom moments, but you could be putting yourself in danger if you’re out there?” Dean confirmed. “Did I get that right?”
“I think so,” Cas said.
“Then it’s decided. You should stay. You will stay, right?” Dean asked. “None of that sneaking around not telling us things, okay? I, uh, we want to help you in any way we can.”
“Alright,” Cas agreed. “I promise I’m not keeping any more secrets or running away.”
“Good,” Dean said.
The fourth lesson (angel biology)
“Hey, buddy. How’re you feeling?” Dean asked. Cas had mostly been in his own room for the last two days, and Dean was trying to not be a mother hen about it all, but he couldn’t help worrying about Cas and checking on him a few times a day.
“I’m fine, Dean. I keep having hot flashes all over my body. I haven’t spent the mating season in a human body before, which means the experience is… overwhelming,” Cas said. He sat up in his bed, trench coat and all, and seemed to just exist instead of trying to distract himself. “My genitals keep pulsing along with the hot flashes.”
“Woah, thanks for that image,” Dean muttered, but now he couldn’t stop thinking about exploring that pulsing a little closer. “Have you tried, you know, doing it yourself?”
Dean tried to get his point across without having to spell it out, but Cas being Cas didn’t pick up the meaning.
“Doing what, Dean?” Cas asked.
“You know what I mean. Masturbating. Pleasuring yourself. Getting yourself off. It could relieve a little of the pulsing,” Dean sighed.
“The pulsing isn’t only because of arousal, Dean. My knot wants to lock inside another body, and it won’t be satisfied with only my hand,” Cas said, casually.
“Your what?” Dean asked, although he had a feeling this would be another explanation that would make him feel either horribly stupid, incredibly turned on, or both.
“My penis has a knot at the base, like the canines on Earth. It would lock me inside my partner just before my release and keep me locked with them to ensure the mating is completed,” Cas explained, looking at Dean.
“Wha… How long, how long does the, uh, locking last?” Dean asked, stunned, and as he had expected, turned on by the mental image.
“It depends on how long the copulation has lasted, how strong the release was, compatibility with the partner, and several other factors. It can be anything from a few minutes to almost an hour. I’ve heard that with a compatible partner, the locking will often lead right into another mating after the refractory period has passed,” Cas said.
“Oh,” Dean gasped. He could feel his own cock getting interested in his jeans and he pressed his thighs together. “That’s… uh… that sounds awesome. For the parties involved I mean.”
“I expect it would be intense and pleasurable with the right partner,” Cas nodded, watching Dean. “Mating season with a bonded mate has been described as feeling like nothing else.”
“I, uh, have to take care of something,” Dean said, pointing towards the door. His skin had started prickling under his clothes. “Hope you’re able to deal with the stuff, Cas.”
Then Dean escaped the room before Cas could stop him. He knew he was being really fucking obvious with his feelings for Cas, but right now he didn’t care. Maybe they could finally talk about it when Cas was feeling better.
The fifth lesson (grace bonding)
A few words out of Cas’ explanation were ringing in Dean’s ears when he lay in his bed after an embarrassingly quick orgasm.
Mating season with a bonded mate.
Bonded mate.
Dean couldn’t tell what that meant, but he had also left Cas’ room before he could get his upstairs brain to work enough to wonder about it. Trying his best to not think about how Cas had once described them sharing a more profound bond, Dean closed his eyes.
His skin had started tingling. It was like pins and needles, only… pleasurable. It wasn’t arousal as much as need for something he couldn’t place. His body was sending messages Dean had never before experienced, and although it wasn’t painful, it was strange.
Jacking off had apparently made the feeling stronger.
When the first flash of heat all over his body happened, Dean gasped. His cock was, well, there was no better word for it, pulsing.
“Oh shit,” Dean said aloud.
This time he didn’t bother knocking when he entered Cas’ room but slammed the door open. Cas looked alarmed when Dean marched to stand next to his bed.
“Do you have an explanation for why I’m feeling your symptoms?” Dean asked strictly, arms crossed across his chest. “Tingling, hot flashes, pulsing. I don’t have the wing thing, probably because I don’t fucking have wings.”
“Dean…” Cas said, looking almost scared. That wasn’t right. Cas never looked scared.
“Spit it out. I can see on your face that you know something. Have you, I don’t know, infected me somehow?” Dean asked, frowning.
Cas looked up to his eyes, looking shameful, and turned his head away. It was a vulnerable gesture and took some wind out of Dean’s sails.
“In a way I have,” Cas said. “Although it was years ago and quite unintentional.”
“Explain,” Dean said and sat on Cas’ bed.
“I don’t know if you noticed me talking about bonded mates earlier,” Cas said and glanced at Dean. Dean nodded. “Angels can form grace bonds with each other. It is involuntary, and an angel cannot choose with whom they bond. The graces call to each other and during a contact the graces are joined together. This usually means that the need to be with the bonded mate is overwhelming during the mating seasons, because the graces can rejoin in a meaningful way.”
“That’s all very interesting, Cas, but what has that got to do with me?” Dean asked. He wanted to touch Cas but he kept his hands to himself.
“I assure you that I did not know angels and humans can form a bond. I don’t think anyone could foresee the consequences of that. Maybe no one knew before…” Cas’ voice faded away. Something clicked in place in Dean’s brain.
“Before you pulled me out of Hell,” he finished the sentence and felt shudders go through his body. Holy shit, that explained a lot. Absentmindedly Dean rubbed his left shoulder and upper arm.
“Your soul attached to me, wrapped itself around me on the way out, and… I had no choice in the matter. I’m sorry, Dean. I never meant… I cannot…”
“Shhh, you said it was unintentional,” Dean said and without meaning to do it put his hand on top of Cas’.
It was as if a group of little butterflies and sparklers had been set free under his skin and all over inside him.
“Dean,” Cas gasped.
The practical demonstrations
White buzzing noise filled Dean’s ears and his mind bounced from one thought to another. He shook his head to clear out his thoughts but didn’t remove his hand.
“Tell me, what would theoretically happen if we kissed or had sex right now?” Dean said, leaning closer to Cas who looked at him alarmed. The pulsing between Dean’s legs was getting more intense, although it was now overshadowed by the other feelings all over his body.
“Dean, you don’t… you cannot mean… I can’t…” Cas stammered. It was amazing to see Cas be speechless for once.
“Don’t you want to?” Dean asked and leaned backwards again. “I can fuck off if you’d prefer to be alone.”
Cas grasped Dean’s hand and stopped him from going further.
“I want to. But I thought you wouldn’t,” Cas said. “Dean, my grace is attached to you. I’m in love with you. I cannot have sex with you one time, never mind spend the mating season with you, and then go back to being friends.”
The buzzing in Dean’s ears intensified when Dean processed the words.
“Cas, me neither,” Dean said, trying to find the right words to respond to a fucking love confession. “I, uh, don’t want to have a one off either. I’d like a, umm, permanent arrangement if you don’t mind.”
Reacting quicker than Dean had expected, Cas had Dean pulled on the bed and lying under him.
“I hope you have taken in all the lessons I have given you about the subject,” Cas said. “You need to be absolutely sure.”
“I am,” Dean said, feeling more sure about taking the step than about any decision in his life. Hell, he was basically a soulmate to the love of his fucking life. It didn’t get better than that.
Cas kissed him. If a simple touch had made sparks erupt under his skin, the kiss woke up entire galaxies inside him. When Cas managed to undress both of them and had all of that naked skin pressed against him, Dean lost all ability to form words. New nebulae were born that moment, Dean was sure of it.
Maybe with anyone else Dean would have been embarrassed how quickly he could be turned into blubbering mess by a few fingers in his ass and Cas’ mouth sucking him off, but by that point Dean felt his soul was comfortably snuggled against Cas’ grace and earthly things like shame didn’t hold any meaning anymore. He could feel all of Cas’ essence like it was his own, and he knew Cas could feel him just the same.
“Dean?” Cas asked after giving Dean one spectacular orgasm and already well on the way to heightened pleasure again. “My wings are itching. Would you mind if I… let them out in this plane of existence?”
“Only if I can touch them,” Dean perked up.
“You’re allowed to touch all of me, Dean,” Cas stated.
“Oh shit, did I fuck up?” Dean realized. “You talked about taking care of your wings as foreplay? Should we have done that?”
Cas gave him a brilliant smile.
“No matter, Dean, we have many days left until the season ends. We’ll have an opportunity to do that later,” Cas said.
The wings were beautiful. Black like ink but reflecting all the colors of the spectrum like oil spilled on water. They gave Dean something to hold on to when Cas was pushing inside him or to ground himself when everything he was feeling threatened to overwhelm him. They were indeed soft under his touch.
If Dean had thought sex had ever been intense in his life before, none of it compared to the feeling of Cas pushing his knot inside Dean. He was submerged by the feeling of being wanted, Cas’ cock pulsing inside him and his own between his legs, and all the while Dean’s soul was singing from joy. Dean couldn’t say when he orgasmed, or how many times, only that there was a feeling of belonging he couldn’t ever remember experiencing before.
When Cas’ knot was locked inside him afterwards, Dean had time to learn how the feathers felt on different parts of Cas’ wings and how Cas reacted to him touching them. Every once in a while Dean found a place that made Cas gasp against his neck or moan softly. One touch led to another and Cas hardly had time to unlock from Dean, before the pulsing and tingling grew stronger again, and Cas began to move against him again.
After the most urgent need had passed, and Dean couldn’t have said what time or even weekday it was, Dean sat cross legged behind Cas grooming his wings gently and marveling at the trust Cas had for him. Cas had pulled out his phone after a light on it had signaled a new message.
“Oh,” Cas said.
“What?” Dean asked, absentmindedly and smoothed a few wonky feathers out of a messy place on one wing, spreading wing oil on it to cover the remaining ones.
“Sam sent me a message. He says he has gone to stay with Eileen for a few days and says he’s happy for us,” Cas said, showing Dean the message.
“Fuck,” Dean leaned his forehead against Cas’ back. “He’s going to be unbearable when he comes back.”
“Maybe so, but I’m glad he doesn’t have any objections about us,” Cas said, turning his head to look at Dean. “I have spent a lot of time explaining angel mating rituals to you, but I feel uncertain about my competence in human relationships.”
A worried frown had appeared on Cas’ forehead and Dean wanted nothing more than to kiss it away.
“Hey, I’m not the most glowing example of successful human relationships either. We’ll figure it out. Together,” Dean said and kissed Cas simply because he could. “I don’t think we have any references to how the human angel mating combo is supposed to proceed, but I trust we can make it work.”
Cas sighed against Dean’s mouth and from the new sparkles under his skin, Dean could tell they were approaching a new wave of mating urge. He pressed down on a sensitive spot he had found earlier on one of the wings and managed to make Cas shudder and twitch.
“Meanwhile, we have the whole bunker to ourselves, so in case you have some angel stuff you haven’t yet demonstrated to me, now would be the perfect time.”
“Yes,” Cas said, smiling at him, making Dean’s heartbeat a little faster. “I think I have a few ideas.”
-fin-