Posted originally on the Archive_of_Our_Own at https://archiveofourown.org/
works/12786756.
  Rating:
      Explicit
  Archive Warning:
      Underage
  Category:
      F/F
  Fandom:
      Supernatural
  Relationship:
      Dean_Winchester/Sam_Winchester
  Additional Tags:
      Femslash, Alpha/Beta/Omega_Dynamics, Claiming, Rutting, First_Time, True
      Mates, Attempted_Sexual_Assault_by_OMC, Spoiler:_He_Gets_Shot_in_the
      Dick, BAMF_Sam_Winchester, Female_Alpha, Female_Alpha/Female_Omega_-
      Freeform, John_Winchester_Loves_His_Children_and_Does_His_Best
  Series:
      Part 4 of Open_Verse
  Collections:
      SPN_ABO_Bingo
  Stats:
      Published: 2017-11-22 Words: 3723
****** Juxtaposition ******
by IndridGrey
Summary
     What if Sam hadn't woken John up that night when D was 17? A smutty
     au of an au.
     (Probably should at least read the first story of this series first)
Notes
See the end of the work for notes
An insistent tapping noise dragged D out of her sleep.  She always slept well
in the car, surrounded by strong pack-smell, so it was a slow drift into
consciousness.  It didn’t feel like it was day time yet.  Maybe Dad was there
to bring her inside and explain why he had wanted her to sleep outside in the
first place.
"Omega," was cooed a foot away from her head and suddenly she was wide fucking
awake.
Oh, God.
Right outside the car, peering in at her, were two alphas—both male, white,
late twenties.  The slightly closer one continued tapping the window and
grinned at her when he noticed that she was alert.  The light from the motel
exterior was just enough that it cast deep shadows on his face and the effect
was chilling combined with her seeing him upside down.
"Hey, there," he greeted.  "What's a pretty O like you doing in a place like
this all on your lonesome?  Your alpha not taking good care of you?"
The other alpha ducked down next to his friend.  "We'd take good care of you,
sweetheart.  Just have to let us in."
D was frozen, gaze darting between them, assessing.  Neither seemed armed
(yet), so she inched her hand up towards the glove box where her gun was
stashed.
“That’s right,” alpha 1 misunderstood, “let us in.”
Violent nausea ripped through D as she lurched up and away from the door—from
the lock—before her O did anything dangerous.  She tipped herself into the
backseat and jarred her wrist as she landed awkwardly, half in the footwells.
“What the fuck?”  The alpha sounded baffled and D prayed that they would think
they’d smelled wrong.  Most omegas couldn’t resist alpha commands, after all. 
No dice, though, because they just moved a foot and a half to stare at her some
more, their faces scrunched in confused anger.
“Open the door, omega.”
Sickness roiled through her, goosebumps raised all up her arms and neck, and
cold sweat beaded up.  Fuck, she’d left her gun, where the fuck was her phone? 
She needed to call Dad—
“Get the fuck away from her.”
D peeked over the back of the seat and gaped.  Her thirteen-year-old baby
sister was standing in front of their room, barefoot in worn pajamas, with a
pistol aimed squarely at the head of alpha 1.  Something about her stance, the
way she bared her teeth, the fury in her tone, struck a chord with D’s O and
she felt safe even though Sam was scrawny and up against two adults.
“Or what, runt?”  With both alphas focused on Sam, the last tendrils of
discomfort from disobeying faded.  D slowly started moving back over the seat
to get to her gun.
“Or I shoot.”  Sam sounded dead serious, and D’s breath caught as goosebumps
rippled through her again, but this time they were accompanied by a warm
tugging sensation in her abdomen.  Well that was super weird.
One of the alphas laughed and D snapped back to reality.
“You’re not even popped, little girl, you don’t have the balls.  Now run back
to mommy.  Unless you wanna get fucked alongside this bitch.”
D lunged for the glovebox with renewed panic, but a shot rang out and the
talker dropped with a scream.  Oh fuck oh fuck Sam just shot someone.  She
scrabbled for the lock and burst out of the car.  The other alpha was
hightailing it and D wrapped her arms around her sister to haul her away from
kicking the downed alpha.  Sam snarled and spat at the screaming man as D
dragged her back and thank god at least he was still alive.  Maybe not for
long, though, gauging by the rapidly growing pool of blood.
The door to their room slammed open and their Dad was there, wild-eyed and
armed with a shotgun.  His gaze skipped over the Impala, the alpha, and he
visibly relaxed when he saw his daughters alive and kicking, literally in Sam’s
case.
“He was gonna rape her.”  Sam let out an ugly laugh and finally stopped
struggling.  She looked up at D and gave her a feral grin.  “So I shot him in
the dick.”
“Jesus Christ, Sam,” their dad whispered.  He leaned next to the alpha and
checked his pulse even though the man was sobbing loudly.  “I have to get him
to the hospital before he bleeds out and you become a murderer.  You could have
shot his arm for fuck’s sa—no, we’ll talk about this later.  Get in the room,
both of you.”
She tugged her sister, who came easily after spitting once more.  The room was
cool and peaceful, a sharp contrast from outside.  Only the lamp between the
beds was on, probably from Dad looking for Sam before getting his gun.  Her dad
pocketed his wallet and held his hand out for the keys.  She really didn’t want
to offer to help carry her would-be rapist to the car and was glad when he just
barked out for them to lock the door, not answer if the police came by, and for
god’s sake not shoot anyone or burn the place down while he was gone.
D watched through the window as he lugged the alpha into the car and then
peeled out.  One last glance at the blood glistening on the rough asphalt and
she snapped the curtains closed.  She turned to Sam.
“What if you killed a civilian?”
Sam’s hand was shaking a little as she dropped her gun onto the little table by
the door.  “I don’t care.  He deserved it.”
D didn’t exactly have a comeback for that.  She wasn’t sure she disagreed,
although she was sure that their Dad would; he always told them to leave the
humans up to the justice system.
She watched Sam doublecheck the salt lines.  D thought the shaking may be
shock.  Sam was a good kid, and she had barely hurt supernatural things, let
alone a human.  D was in shock.  And really confused because under the shock
was more of that sense of safety and warm tugging feeling, and she—her O—
Something may be wrong with her, even more than the suppressant-stunted puberty
thing, because whatever was going on, she was about 120% sure it wasn’t
supposed to happen in regards to one’s kid sister.
Her worries took a backburner when thin arms wrapped around her middle and Sam
snuggled into her chest.  Sleep-mussed hair tickled D’s chin and she leaned
into it and rubbed her hands up and down her sister’s back.
“It’s going to be okay, Sammy.”
She was in the middle of taking a deep inhale of Sam-scent when it changed, and
she barely kept from moving away out of surprise.  It was still Sam, but
something new was edging in.  The point of Sam’s nose dug into her sternum
before it dragged up to the curve of her neck.  D’s shuddering breath was
exhibit 3 in the case of something being wrong with her.
“What if it happens again?  What if more people think they can take you from
me?”
“I’m not going anywhere.”
“I know,” Sam growled, and D felt it in her own throat.  “That’s not the
problem.  What happens when other people don’t know that?”
"There's not a whole lot we can do about that.  I just can't let people get the
drop on me, y'know?  Just like with monsters."
Sam's nuzzling stilled and the change in her scent turned sharper.  D could
almost put her finger on what it was.
"Sam?"
Her arms tightened around D's waist and her voice came in a whisper, "If I
could help, you'd let me, right?"
"Of course."
Sam leaned back and looked up at D with a nervous look and blown pupils.  She
licked her lips.  The tug in D's tummy was exhibit 4.  Sam stood up on her
tiptoes and her hands retreated from around D to move onto her face.  Things
clicked into place when Sam pulled her down slightly into a clumsy kiss.
Rut.  Sam smelled like a rutting alpha.  But ruts weren't supposed to happen
until an alpha's knot popped, and Sam's hadn't.
That didn't seem to matter to Sam's body, though, because the scent was strong
now and D could taste it on Sam's tongue as it breached her mouth.  D pulled
away with a gasp and weak knees, and all the complicated things her insides
were doing were exhibits 5 to about 20.
"D, please.  Let me?  I know you feel it.  You're mine, no one else's."
So not only did D have the hots for her baby sister, but the feelings were
reciprocated.  She should really send Sam to go take a cold shower and call
their dad to ask what to do because whatever Sam's end goal was, D should not
be allowing her to get anywhere near it.
Sam drew close again and pressed her nose hard against D's neck, where a scent
gland was doing its best to get her mated despite her suppressants.  Sam let
out a little growl and D's thighs trembled.  She should be the bigger person
and push her sister away.  Or lie.  Or tell her to pause whatever this was
until she was even remotely of age.  So many ways to be responsible and D
probably wasn't going to do any of them.  She didn't want to stop Sam.  She’d
been Sam’s since before the kid was even born; what was the harm in making that
more obvious?
She buried a hand in chestnut waves to pull Sam back a little and placed a
chaste kiss on her alpha’s open mouth.
"Yeah.  Okay, Sammy.  Whatever you want."
"What if I want to fuck you?"
D shivered.  She’d never heard Sam say something like that, and it was awkward
in her mouth because Sam was still so young—fuck, so little, how would sex even
work—
“Whatever you want, Sammy.”
Sam started pushing her towards the bed furthest in the room and D sat down on
the edge when directed.  Arranged like this, Sam was very slightly taller than
her, and she was using that height to stare at D, assessing.  She nodded to
herself and looped her arms over D’s shoulders.
“I want you to be mine.”
“Already am, baby girl.  Always have been.”  Considering the ease and honesty
of her response, D really should have seen this coming.
“I want other people to know!  So they know they’ll have to go through me
before they try to mess with you.”
“We can get me a collar.”
Sam made a frustrated noise and D couldn’t help the small, teasing smile.
“Just nothing that’s all girly and shit.  You try to get me something pink and
sparkly, and being my alpha won’t save you from getting your ass kicked.”  Sam
blushed, the scent of her rut deepened, and D’s O was rising to the call.  She
snagged a finger in the elastic waistband of Sam’s pajama pants and Sam was
shaking like a leaf as D whispered against her lips.  “You can come in me if
you want”— Sam whimpered—“but try not to do a bite, okay?  I wanna save that
for when you’re all grown up and bigger than me.”
“But you’ll wear a collar?”  D nodded and Sam grabbed her face, holding her in
place.  “And you’ll let me—please, D,” came out almost as a whine.
Her answer was to pull Sam deep into another kiss.  She multitasked with giving
silent instruction for kissing skills and shrugging out of her jacket and outer
shirt.  Sam practically crashed down into her when D sucked on her tongue, and
D broke away with a laugh.  Sam pouted for the split second before D got the
last of her shirts off, and then she was staring intently at the flimsy
bralette covering D’s almost non-existent breasts.  D barely held in another
laugh and tugged at Sam’s shirt, prompting her to take it off.
D was struck again by how little Sam still was—her nipples were hard in the
cool motel air, and her breasts were firm under D’s tongue, barely past the
budding stage—but the rut overwhelmed the immature alpha scent and broadcasted
readiness, desperation to mate.  Sam’s hands were fumbling but determined at
D’s belt buckle until D closed ginger teeth on a tiny nipple and they relocated
to grab at D’s hair.
She pulled away with a quiet pop and tucked Sam’s hair back, out of her
flushed, dazed face.  She pressed a quick kiss onto slack lips and stroked her
hair a couple times.  Sam grabbed for her and made a hurt, dismayed noise when
D leaned back.
“Shh, it’s okay.  In one of the side pockets of my duffel, there’s a little
bottle of lube, can you go get it for me?”
It took a light smack on the ass to get Sam moving, but she went without
complaint.  D stripped out of the rest of her clothes, threw back the covers on
the bed, and managed a make-shift nest before Sam turned back towards the bed,
lube in hand.
Her O wanted to preen under the look on Sam’s face.  She was 17 and was barely
more developed than Sam, but you wouldn’t have guessed it from the way Sam
stared, and a nervousness in her eased.  She lifted a hand to beckon Sam, and
her sister nearly tripped over herself in her haste.
Sam clutched the lube to her chest as D undid her pajama pants string and
tugged them and her panties down.  D watched the garments sink to the floor and
watched Sam’s erection bob as she stepped out of them.  Her sister gasped
loudly when D cupped her hand under the hot shaft and stroked.  She only made a
couple teasing passes before she took the lube and climbed onto the bed.
The lamplight caught on the honey highlights in Sam’s hair and wide, nervous
eyes as she climbed on after D settled.  She reminded D of a puppy, all eager
and naive and waiting for a cue.  D brought her legs up and spread wide,
putting herself on display, and her stomach fluttered and her pulse ticked up
even more at the look Sam gave her.  She could smell herself almost as strong
as she could Sam, now—both of their scents were slightly off, but they mixed
into something intoxicating nonetheless.
Sam watched with rapt attention as D squirted lube onto her own fingertips and
reached between her legs.  It was unpleasantly cold against her blood-swollen
clit, but warmed from her body as she spread it over her labia and entrance. 
Sam sucked in a breath when she slipped a finger inside herself, and D smiled. 
She pulled one of Sam’s hands onto her raised thigh, dabbed some lube on Sam’s
fingers, capped the bottle, and guided Sam between her legs.  She dragged her
own finger out and up to rest just right on her clit hood and tugged Sam’s hand
even closer.
“Gently,” she instructed, and Sam nodded so hard her hair bounced and fell
forward.  D watched Sam’s awed expression as she slid a finger inside and D
clenched.  Two more thin fingers in quick succession and D’s hips bucked for
friction and D pulled her sister down for a sloppy kiss.  Sam had no finesse,
just pushed as much of herself as deep as she could into D, and fuck but that
was really doing it for D.
Sam whimpered against D’s tongue and thrust her fingers so rough that D
squeaked.
“D, please.  I gotta—please!”
“I’ve got you, Sammy.”
She pushed Sam’s arm away and tilted her hips before she pulled Sam even
closer.  “Hush, baby sis,” she murmured against Sam’s cheek.  “I’m right here.”
She caught her hips, which had been humping the air like a puppy, and pulled
her down.  Sam ducked her face against D’s throat when D cradled her dick.
“Remember, Sam, no biting.”
They made a few position adjustments and then Sam’s dick brushed her entrance. 
Sam jerked forward and her head jabbed D’s clit, making them both hiss in
discomfort.  D ran a hand down Sam’s flank and guided her back.  This time, Sam
waited until the tip was in before she shoved forward and sank to the hilt in
one rough go.  She barely paused to shift her weight and then she was fucking D
like her life depended on it—which, judging by the growls and harsh grunts and
the thick scent of her rut, she may well have felt like it did.
D clutched her little sister tight and tried to soothe her between her own
whimpers and harsh breathing.  Sam’s fingers had filled her wider and deeper
than her petite cock, but once D got them aligned so that their movements
rubbed D’s tits and clit just right, it more than made up for the difference. 
Plus, it was hot as hell how frantic Sam was to claim her, single-minded focus
and just taking.
It was only a few minutes until the rut scent sharpened even more with
pheromones that made D’s vagina clamp down.  Sam was about to pop—a couple
years too soon, but D would help her through it and maim any shitty teen who
tried to tease Sam for it.  Sam started whimpering against her throat and D
forced her own pleasure to the back burner as she stroked Sam’s shoulders and
hair.  The scent of her impending knotting was tainted by acrid fear.
“Shhh, Sammy, I’m still here.  Don’t be scared.  Let it happen, baby girl. 
Wanna feel your knot in me.”
Another burst of pheromones had D trembling under and around her sister and
then Sam’s scent slid into something richer and D yelped and came when S shoved
hard against her, hitting her clit and then stretching D wider on her knot.
The deep growl gave her enough warning to pull Sam’s face away by her hair,
just in time if the snarl and clenched jaw were anything to go by.  D was
shuddering through the pleasure radiating from her pelvis and she had Sam snug
inside her and she wanted nothing more than to let Sam take the last bit and
mate her, but she couldn’t risk it.  She stroked Sam’s sweaty temples and
basked in the sensation of Sam’s come flooding where her cock couldn’t reach
yet.  Only a few years, and then Sam would be so deep in her, stretching her so
wide, that she wouldn’t be able to think.  Only a few years, and then Sam could
take that one last part of D for herself and mate her.  For now, though, she’d
happily take everything Sam could give, and give everything she could.
Sam finally melted against her and D let her tuck her face by D’s scent gland
again.
“Feel better?”
She still smelled like rut, but it was weak compared to the scents of frantic
sex and newly popped knot.
“Wanna do it again.”
D laughed and stroked her alpha’s head.  “You haven’t even finished coming. 
And once you do, you should try to sleep. It’s the middle of the night.”
“Mmph.”
Sam was quiet and still and D didn’t move until her dick slid out of her, and
even then it was just to shift her weight and pull the sheets up over them. 
She was halfway to sleep under her alpha, full of cum and claim-scented, when
the door opened.
Her eyes shot open and her stomach flipped.  She hadn’t even heard the Impala. 
Not that she’d have been able to hide what she’d allowed to happen from their
dad anyway.  He paused in the door, but came in.  The lamplight that had made
Sam look so beautiful and warm just made him look worn-down.  She watched his
eyes take in the salt lines, the gun on the table, and their clothes on the
floor, before his gaze met hers.
“I’m so sorry.  I’m supposed to look after her, not—”
“It’s not your fault, D.”  He walked over to the bed and stared down at Sam’s
brown waves fanned out everywhere.  “It’s not anyone’s fault.  It was always
going to happen.”  D was about to ask what the hell he was talking about, but
he gave a quiet huff.  “Well, the Mates thing was inevitable.  Sam nearly
killing a man being the jumpstart not so much.”
D clung to what she could process.  “He’s going to be okay?”  At least Sam
wasn’t a killer.  Yet.
“’Okay’ is probably a stretch.  He’ll need a lot of blood, but his pulse was
strong and his breathing was decent when I left.  I overheard them saying that
most of his…manhood was probably too damaged to save.”
“Good.”
D jumped at the quiet assertion and the feel of Sam’s lips against her
collarbone.  Their dad sighed and stared at the wall behind them.
“You and I are going to have a long talk tomorrow, young lady.”
“Ugh.  Pass.”
“No pass.  You can’t go around letting your alpha do stupid shit.  You’ve got
an omega you need to be here, and not in juvie, for.  Talk.  Tomorrow.”
Sam settled further against D with a disgruntled noise and their dad picked up
his bag from its spot next to the couch.
"I’ll sleep in the car.  We need to head out before sunrise in case he regains
consciousness soon and talks, or the police decide to come around, so try to
get some rest, but be decent and ready to go in a few hours.  Night, girls.”
“Night, Dad,” D answered for them both.  She let silence fill the room for a
long few seconds after he closed the door.
“So," Sam finally piped up. "He’s not mad.  That seem kinda weird to you? 
Like, not even surprised.”
“Tomorrow.  We only have a few hours before painfully awkward conversation.”
Sam popped up on locked elbows, eyes alight and round lips quirked.  “You
should help me relax.”
D giggled and pulled her sister down.  Kissed her.  “Yeah, okay.  Then sleep
for real, okay?”
"Sure, sure."
===============================================================================
D's collar ended up being pretty badass, if she said so herself.
 
End Notes
     I'm That Person lol
     For the wincest square on my spnabobingo card
     Concrit welcome. Kudos and comments make my day!! :D
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