Posted originally on the Archive_of_Our_Own at https://archiveofourown.org/
works/10932588.
  Rating:
      Explicit
  Archive Warning:
      Underage
  Category:
      M/M
  Fandom:
      Supernatural
  Relationship:
      Castiel/Dean_Winchester
  Character:
      Dean_Winchester, Castiel, Sam_Winchester, John_Winchester
  Additional Tags:
      Consensual_Underage_Sex, Riding, Drug_Use, First_Time, Shotgunning,
      Alternate_Universe_-_High_School, Tutoring, Punk_Castiel, Nerd_Dean,
      Drunk_John
  Collections:
      Destiel/Sabriel_Smut_Challenge
  Stats:
      Published: 2017-05-17 Words: 4377
****** A Lesson in Anatomy ******
by crowleyhasfeels
Summary
     Dean has the biggest crush on Castiel Krushnic. Castiel is everything
     that Dean isn't. Punk kid with dark eye liner and clothes to match.
     Breaks all the rules and has a sexy girlfriend. So, what the hell
     could he want with Dean, the schools nerd that most people don't even
     give the time of day?
Notes
     I recently finished my first ever long story for DCBB 2017. I am very
     proud of me for doing this. However, I could not have done it without
     NavajolovesDestiel. Without there help, I would have given up long
     before I finished. So, this story is for you. Thank you for keeping
     me going, even though I felt like giving up many times. Thank you. I
     hope that you enjoy this story that I wrote for you.
See the end of the work for more notes
            Dean looked up from the textbook he was reading, hiding beside the
over grown tree that sat off to the side of the school. It was the only place
where he could get any quiet. Inside the school, people were loud or constantly
bugging him for having his head in a book or working ahead on his homework, and
at home, well, home was never quiet. Between the screaming or the television
blaring, or the loud drunken snoring, quiet wasn’t something he got very often.
As he looked up, his eyes locked onto the dark form. Black pants, holding onto
his thin body with bright pink suspenders. It was hot outside, or else he would
also be sporting his leather jacket, the one with all the spikes down the arm.
            Dean’s eyes moved up from the body to his face. Castiel was
beautiful in the darkest of ways. From the way his eye lashes stuck out around
thick eye liner or the way his hair looked like he had never even once
considered brushing it. Most people thought he was a freak or worshipped Satan,
but Dean could see the angel beneath the surface, dark and rebelling. Dean had
dreamed of talking to him, a dream that has lasted for the last three years,
but he never could find his courage. Though he felt Castiel to be an angel,
that did not mean that he wanted anything to do with Dean.
            “Yo,” A voice called from the distance, grabbing both Castiel and
Dean’s attention. Dean’s eyes finally landed on Meg, Castiel’s girlfriend.
            Meg, like Castiel was beautiful. She was the darkness to the light
that was Castiel and somehow, that made them perfect. She was also sporting the
same look as Castiel, minus the suspenders. She did wear her leather jacket,
even through the heat. In fact, Dean was not sure he had ever seen her without
it. “Where you going?”
            “Я собираюсь поговорить с ним,” Castiel called back to her and
Dean’s heart began to race in his chest. He loved when Castiel spoke Russian;
he loved when Castiel spoke at all. Even at seventeen, Castiel had a deep,
gravelly voice that would put most grown men to shame.
            “О проклятом времени,” She shook her head but gave him a smile, at
least, Dean thought it was a smile. It was hard to read any other emotion from
Meg besides angry.
            “Ага-ага,” Castiel waved her off with his hand and she disappeared
back into the school.
            Dean’s eyes went back to Castiel, curious as to where he was
headed. Dean assumed he was ditching school, being as, he rarely came to school
as it was. But when he started walking toward Dean, his mind about short
circuited. He prayed for Castiel to continue past him, disappearing beside the
school to go smoke a cigarette or whatever it was that he did in the shadows,
but that didn’t happen. Castiel was now standing only feet in front of Dean,
looking down at him through the bluest of eyes. Dean had never realized how
blue they were, not until they made contact with his for the first time.
            “Winchester,” Castiel shoved his hands into his pockets, almost
nervously.
            “Krushnic?” Dean almost stuttered out, not sure how he was supposed
to respond. Was this how they were to talk to each other?
            They looked each other over for a moment before Castiel sat down
across from Dean. He absentmindedly twirled grass between his fingers, eyes
never leaving Dean. Dean was not sure if he was supposed to be worried about
this or not. Castiel had been in lots of fights, but Dean did not know him to
go out of his way to be mean to someone. Normally, the fights appeared to be
self-defense. But what could Castiel want with Dean?
            “I heard through the grapevine,” Castiel finally started talking,
throwing Dean off a little. He was not prepared for words to say back. “You are
good at this school shit.”
            “Um,” Words Dean, use them. The man of your dreams is sitting in
front of you, talking to you and the best you can come up with us um?
            “Глупый,” Castiel mumbled to himself, pushing into the ground to
raise himself to his feet.
            “Yes,” Dean blurted out quickly, not wanting Castiel to go away
just yet. “I am good at all this … school shit.”
            “Yeah?” Castiel raised an eyebrow, a hint of a smile forming over
his face. He looked Dean over a few more times and then sat back down. “This
may sound stupid but are you possibly interested in … maybe, sorta … tutoring
someone?”
            “Oh,” That made a lot of sense. Why else would someone like Castiel
talk to Dean. He needed help. Dean was good at help. School he knew. “I would
love to tutor you.”
            Okay, so that came out a little more eager than Dean had wanted.
But he could tutor Castiel. He would love to tutor Castiel. Anything to get to
actually talk to the boy.
            “Um,” Dean tried to hide the blush that he felt on his cheeks, but
he couldn’t see himself, so he was unaware if he was successful or not. By the
smile that was on Castiel’s face, he assumed that he had been caught. “When
would you like to start?”
            “I can come by your house tonight,” Castiel nodded, as if that were
the perfect answer, but he was wrong.
            “My house?” Dean’s voice dropped into his stomach. No one ever came
to his house. His house was where his dad was.
            “Yeah,” Castiel cocked his head to the side, giving a Dean a look
like maybe Dean was stupid or something. “My house has like twelve people in it
and libraries give me the creeps. So, your house would be best.”
            “Okay,” Dean agreed, though he was going to regret this. Hopefully
if his dad knew that Dean was tutoring someone, he would try and be on his best
behavior. “How about five?”
            “Works for me,” Castiel stood himself up and dug into his pocket,
pulling out a pack of cigarettes and a lighter. He didn’t even wait to be off
school grounds before bringing it to his chapped lips and lighting it. “See you
at five, Dean.”
_____
 
            Dean spent all of his time after school cleaning up their house.
Sam and Dean kept their room pretty clean, but the rest of their house was not
so taken care of. Dean tried to keep it as clean as possible, but John was a
slob and cleaning up after him wasn’t always Dean’s number one priority.
However, the last thing Castiel needed to see was the house covered in beer
bottles and take out containers.
            “Feeling like cleaning today?” Sam asked as he walked in the front
door. He was three years younger than Dean and a Freshman. You wouldn’t know it
though, since he had recently hit a growth spurt and was currently an inch
taller than Dean.
            “I am tutoring someone later,” Dean looked at his brother, showing
how worried he was about this. “I don’t want them to walk into our garbage
dump.”
            “Good point,” Sam set his backpack down but the front door and toed
off his shoes. “Who are you tutoring?”
            “Castiel Krushnic,” Dean mumbled, hoping Sam would miss it all
together. Dean didn’t openly talk about Castiel but Sam was well aware of his
crush on the boy.
            “Seriously?” Sam’s voice showed sudden excitement. “That is so
cool. You gonna tell him you like him?”
            “Absolutely not,” Dean shook his head and raised his finger to
point at his brother. “And if you open your mouth about it, I will hurt you.”
            “Uh huh,” Sam rolled his eyes and headed toward the kitchen.
“Whatever you say Dean. Castiel and Dean, sitting in a tree …”
            Sam’s voice trailed off as he disappeared around the corner,
leaving Dean flushed and embarrassed. What was he thinking allowing for Castiel
to come to his home? Sam knew about his crush and Dean seemed to be a blushing
idiot when it comes to the boy, how was he supposed to hide all of that from
father?
            Luckily Dean asked him to be here at five. John did not get off
work until five and would not be home until a little after fife thirty. Maybe
if they had company, John would hold off on the drinking, at least until
Castiel left. Hopefully.
_____
 
            By five fifteen, Dean was worried. Castiel had yet to show up and
John was going to be home soon. He was about to go into a complete panic when
there was a knock at the door. Dean made his way across the living room, faster
than he normally would and swung open the door. Castiel didn’t even give Dean a
chance to process his arrival or speak, instead, as soon as the door opened, he
made his way inside and flung himself down onto the couch.
            “So, this is your digs?” Castiel pulled his feet up and put his
unlaced shoes onto the coffee table.
            “Uh, yeah.” Dean nodded, moving into the living room and sitting
down on the opposite end of the couch.
            “It’s good,” Castiel looked around a little more, taking it all in.
There wasn’t much. Random pictures hung on the wall, along with some old guns
and his father’s military stuff. There were books piled on tables and an old
television on the other side of the room. It looked like a single man lived
here, which was kind of true. “Looks … lived in.”
            “Doesn’t your house look lived in?” Dean inquired.
            “Nah,” Castiel pulled his feet off the table and pulled one leg up
to rest on his knee. “My house is so spotless it looks like some real estate
show home. No signs of life.”
            “But you said twelve people live there,” Had Dean heard him
incorrectly earlier?
            “That is what makes it so bad,” Cas nodded. “No house with twelve
people in it should be as clean as my home is.”
            “Oh,” Dean was not good at small talk. What did someone say to
that? “You didn’t bring a backpack.”
            “Was I supposed to?”
            “Kind of hard to teach you if I don’t know what you are struggling
in.”
            “Think of any subject you can think of,” Cas instructed. “And now
you know what I am struggling with.”
            “Okay,” Dean nodded, feeling caught off guard and unprepared. How
was he supposed to tutor someone without a guide for what needed to be taught?
“Is there anything specific you wanted to work on today?”
            Castiel seemed to contemplate his answer. Dean wondered just how
many classes Castiel was failing. Most people did not ask for help or for a
tutor if you were not at least failing one class. By Castiel’s previous answer,
Dean now assumed it was more than one. “Anatomy.”
            “Okay,” Dean nodded. He hadn’t taken an anatomy class in a while
but he had passed it with flying colors. Only problem was, he did not really
have an anatomy book.
            “I don’t have the anatomy book,” Dean admitted finally. “Did you at
least bring that with you?”
            “Yeah,” Cas laughed, holding his arms out to show himself off.
“Where exactly did I put that damn book?”
            “How the hell am I supposed to tutor you in anatomy if there is no
book?” Dean asked, almost angry but Castiel’s lack of desire to be prepared?
            Before Castiel could answer, the front door swung open and John
entered. It did not take long for the smell of grease and alcohol to fill the
air. He hoped that Castiel did not smell it but it was hard to miss.
            “Who the fuck is this?” John looked over the boy sitting on the
couch, covered from head to toe in black, aside from the hot pink suspenders.
            “This is Castiel,” Dean sort of introduced him. “I am tutoring
him.”
            “And you couldn’t do that at school?” John obviously was trying to
figure out why Dean had gotten in the way of him and the beer that was in the
fridge.       
            “The school is closed at night,” Dean was quick to answer, making
sure they were clean and to the point. If there was one thing John Winchester
hated, it was people who beat around the bush.
            “Well take it upstairs or outback,” John instructed, not giving any
more reason before disappearing into the kitchen.
            “Um,” Dean shifted in his seat, feeling a little more than
embarrassed. “Want to go out back? I’d say we could study in my room but that
is where my annoying little brother is.”
            “Whatever,” Castiel rose to his feet and waited to follow Dean’s
lead.
_____
 
            Once they were outside and settled, they sat quietly. Dean was not
sure where to begin and Castiel did not seem to be of any help.
            “So,” Dean began, rubbing is slightly sweaty palms together. “What
about anatomy are you having trouble with?”
            “The male body,” Castiel leaned back in his seat.
            “Um,” Dean was completely out of his element. “Maybe we should pick
a different topic. Without a book, I don’t know how much help I will be.”
            “Or,” Castiel looked around the back yard and then stood up. “You
could show me the inside of this bomb ass tree house.”
            “It’s not that great,” Dean looked over at the tree house. His
father had built it back when their mother was still alive, back when he was
still a good dad. “I haven’t even been inside of it for years.”
            “Well today is the day then,” Castiel smiled back at Dean before
making his way up the ladder to the tree house. Dean was wary about it but
soon, he was following right behind.
            “See,” Dean looked around the inside of the tree house. There were
random toys scattered about. “It’s nothing great.”
            “Looks just as lived in as your house does,” Castiel noted, taking
a seat in the middle of the tree house and reaching into his pocket. Dean
assumed he was going to pull out a cigarette like earlier, but this looked a
little different. “You mind?”
            “Uh,” Shit, Dean was going to get in so much trouble. Not just from
his father. He was a good kid who never did anything wrong. Now, here was Cas,
the bad boy of the school, holding out …. What? Drugs? Is it drugs? How was
this even happening? “Sure.”
            Castiel moved, what Dean assumed was a joint, to his mouth and lit
it up. It did not take long for the smell to take over the tree house and
Dean’s fear was at an all time high. What if his father could smell it? He
would beat the shit out of Dean for this.
            “You need to relax,” Castiel reached up and pulled Dean down,
causing Dean to land in his lap. “Try this.”
            Castiel pulled the joint to his lips again and inhaled. Dean went
to pull away, but Castiel held onto him. Dean was about to try and get away
again when Cas’ mouth connected with his own. That was when Cas exhaled,
filling Dean’s mouth with smoke. Dean coughed immediately, inhaling a small
amount. Shit.
            “What did you just do?” Dean wasn’t sure how to feel at the moment.
On one hand, he had just tried majiuana for the first time, against his will.
But on the other hand, the boy he had been crushing over for the last three
years had just basically kissed him.
            “I kissed you,” Castiel laughed, throwing his head back. “With
pot.”
            “Okay,” Dean nodded. At least Castiel was honest.
            “Can I do it again?” Castiel asked.
            Dean could not answer out loud. His entire heart was in his throat,
beating so loudly that he was sure Castiel could hear it. He tried to speak,
whatever but nothing came. So, he nodded his head. He could do that much at
least.
            Castiel took another drag of the joint and quickly pushed his lips
to Dean’s again, exhaling into his mouth. Dean tried not to cough hard this
time, but he couldn’t help it. He inhaled more this time which only made the
cough that much worse. Castiel did this one more time until Dean finally
stopped him, pushing his hand down to stop the joint from connecting with his
mouth.
            “Stop,” Dean instructed, and Castiel set the joint down beside him.
            “Sorry,” Castiel apologized, but that was not what Dean was looking
for.
            “No,” Dean shook his head, trying to keep it on his neck. He felt
that if Castiel was not holding him, he would fall right through the floor of
the treehouse. “I can’t smoke anymore but you don’t have to stop kissing me.”
            “Really?” Castiel’s blue eyes lit up and Dean answered him by
pressing his lips hard against Castiel’s. Castiel brought his arms up and held
Dean tightly to himself before shifting so that they were both laying on the
ground, Castiel slightly on top of Dean.
            “Dean?” Castiel pulled back after a few minutes, hair more a mess
than usual, face just as red as Dean imagined his own to be. “I have to tell
you something.”
            “Okay,” Dean shifted, but Castiel kept him pretty pinned to the
ground beneath him.
            “I’m actually,” Castiel looked away for a moment before making eye
contact with Dean, “not failing any classes. I do pretty good with school
work?”
            “What?” Dean tried to sit up but Castiel would not let him. “Then
why did you ask for me to tutor you?”
            “So, that I could spend time with you,” Castiel admitted, his eyes
showing a vulnerability that Dean never expected to see.
            “What about Meg?” Dean wondered aloud. They had been together for
like ever.
            “What about Meg?” Castiel questioned back.
            “She is your girlfriend,” Dean was more than confused.
            “Wow,” Castiel laughed, a full body laugh that caused Dean’s body
to move with his own. This caused more excitement than Dean had expected, his
cock straining against his jeans, pushing right into Castiel’s leg. “Meg is
like my sister.”
            “I thought you two were…” Castiel shook his head before Dean could
finish his sentence.
            “Nope,” Castiel laughed again, not as hard as before. “I am one
hundred percent gay and Meg have a vagina … I think. I’ve never actually seen
her naked.” Castiel shook his head, his mind seeming lost in thought. “I’ll
have to ask her for nudes later.”
            “So,” Dean shifted back into Castiel. “You are gay?”
            “Yes,” Castiel nodded, leaning in and kissing Dean, this time
softly. “And even though this seems to be going good now, I am really hoping
that you might possibly be gay as well.”
            Dean pushed his cock up into Castiel’s leg, hoping that it would
give him the answer that he was looking for. Castiel seemed to get the message
loud and clear, grinding back down into Dean.      
            “Anyways,” Castiel leaned down and began to trail kisses down
Dean’s face and neck. “You were going to teach me about anatomy?”
            “Uh huh,” Dean’s eyes were in the back of his head, so many
emotions running through his mind.
            “Dean?” Castiel’s voice growled into his ear.
            “Yeah?”
            “How many guys have you been with?” It was a simple enough question
but Dean felt sad to admit the number.
            “None,” Dean didn’t open his eyes, he did not want to see the look
in Castiel’s eyes.
            “What about girls?” Castiel continued with the questions.
            “None,” Wow, Dean was pathetic. Castiel was going to realize this
and disappear, leaving Dean a mess in his childhood treehouse.
            “So,” Castiel ran his hand down Dean’s stomach until it reached the
top of his jeans. “No one but you has had the pleasure of touching your cock?”
            “Uh huh,” Dean finally opened his eyes, only to be met with the
lust blown ones Cas was sporting.
            “God,” Castiel groaned.
            Castiel reached under Dean’s shirt, pulling himself up enough so
that he could work the shirt over his head. Dean tried to reach out and remove
Castiel’s shirt, but Castiel stopped him, leaning in and kissing along Dean’s
stomach. Dean’s body arched off the ground at the feeling. No one had ever
touched him the way Castiel was. The most Dean had ever done with anyone was
kiss, and that was a girl, of which he learned, he had no interest in.
            Castiel nibbled around Dean’s stomach, working up toward his
nipples and biting down on one, his hand moving up to lightly pinch at his
other nipple. Dean felt like he was going to come in his pants but he fought
it. He couldn’t be that guy. He had to hold out. Castiel wouldn’t want him if
he came too fast.
            “Cas,” Dean moved, the name sounding good coming off his tongue.
            “Mmm,” Castiel moaned around his nipple before moving back down to
his stomach. “Again.”
            “Cas,” Dean said a little louder, lifting his hips to help Cas pull
his jeans down as Cas pulled at the buttons.
            “You are more perfect than I imagined,” Castiel whispered against
Dean’s body as his mouth connected with Dean hips, kissing and nibbling at the
skin.
            “Oh God,” Dean cried out, unable to contain himself.
            Dean’s body couldn’t hold still, every inch of him shaking as he
came against his boxers. He wanted to cry, scared that Castiel was going to
leave because of it but Castiel didn’t move away from Dean. He worked his way
back up to Dean’s lips and kissed him slowly.
            “You are so damn wonderful,” Castiel moaned against his mouth.
            “But I …” Dean began, ready to argue but Castiel put a finger
against his lips to stop him.
            “Shhh,” Castiel sat up and pulled off his own shirt, tossing it on
top of Dean’s. He then removed his pants and boxers, leaving himself naked
above Dean. Castiel removed Dean’s sticky boxers and tossed them to the side
before laying down on his again. Dean’s cock twitched, slowly working itself
back to the hardness that it was before. “This isn’t over yet.”
            “I don’t know if I can …” Dean tried to find the right words. He
had never had sex, it could be painful, he was sure it was going to be painful.
            “Don’t worry,” Castiel smiled down at Dean. “I’ve got this. Touch
yourself.”
            Dean reached down and took his half hard cock into his hands. It
was still sensitive but he fought through the desire to pull his hand away.
While he stroked, Castiel dug through the pockets of his pants and pulled out a
packet of a lube and a condom. Dean was not ready for this. He wasn’t ready for
the pain but he wasn’t going to say no and send Castiel away.
            Castiel set the condom aside and opened the packet of lube,
generously coating his fingers. Dean willed his heart to slow down but it only
increased when Castiel reached between his own legs and slowly began to work
his ass open. Dean stroked harder at the sight. He had watched guys do this in
porn before but it was so much hotter happening in front of him.
            Castiel worked his ass with one finger, pushing it in and out until
he was ready for another. By the time Castiel had three fingers inside of
himself, Dean was completely hard again, pre-come leaking out the tip. Castiel
reached down and ran his finger through the slit, causing Dean to hiss.
            “Fuck,” Castiel grabbed the condom and pulled it open with his
teeth. People actually did that? Dean was about to lose it all over again.
            Castiel pulled the condom out of the package and slowly rolled it
over Dean’s cock. Before Dean had time to prepare himself, Castiel lowered
himself down onto Dean’s cock, moaning the most filthy noise Dean had ever
heard before. This caused his cock to twitch and Castiel moaned again.
            “You are so fucking big,” Castiel steadied himself on Dean’s chest.
Dean reached up and grabbed Castiel’s hips to help.
            Castiel moved slow at first, lifting up just slightly before
pushing down. Each time he pulled up, he would pick up speed and slam down just
a little harder until he had a fast rhythm going. Castiel flung his head back,
riding Dean like his life depended on it and Dean was not sure that he was
going to last any longer than before.
            Then Castiel was coming, shooting it across Dean’s stomach and
chest. That was all that it took for Dean to lose complete control. He gripped
Castiel’s hips tightly, worrying for a moment that he was going to leave
bruises but the concern was not high enough for him to stop. He thrust up into
Castiel two times before coming hard, harder than he had ever come in his
entire life.
            It felt like the orgasm lasted for an hour. Dean fell back against
the floor, completely ignoring just how hard he hit it and fought to catch his
breath. Castiel did not make it any easier, collapsing on top of Dean, causing
Dean’s cock to slip out of him.
            “Вы прекрасны,” Castiel whispered against Dean’s skin.
            “Wanna try that one again?” Dean laughed, making a mental note to
learn Russian.
            Castiel looked up at Dean, his black eye liner smeared and running
down the side of his face. Somehow, this only made him hotter.
            “I said, Вы прекрасны.” Castiel laughed.
            “That’s what I thought,” Dean laughed with him, pulling him down
against his skin.
            Silence fell upon them but it wasn’t awkward. Dean no longer felt
afraid that Castiel was going to run away. Mainly because he was naked and limp
on top of his body. But there was something there, something perfect, something
that fit.
            “Chemistry,” Dean said aloud, running his hand through Castiel’s
completely distraught hair.
            “Huh?” Castiel mumbled against his skin.
            “Next time we meet,” Dean looked down at Cas, locking their eyes
together. “We should go over Chemistry.”
            “Hmm,” Castiel contemplated this. “Can we also maybe do a little
anatomy refresher?”
            “Oh definitely,” Dean laughed. “We don’t need you falling behind.”
End Notes
     I don't speak Russian and used a Russian translator app. So, if you
     speak Russian and think this is all wrong, let me know.
Please drop_by_the_archive_and_comment to let the author know if you enjoyed
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