Your Fault

Disclaimer: I do not own Modern Family and have no association with anyone involved in the show. I do not make any money from the writing of this story.

*****

Haley Dunphy felt guilty. She had felt guilty before she had finally let her sister Alex take her anal cherry, which was meant to soothe the guilt of the way she had been treating her, but if anything it just got worse.

No matter how much Alex used her like a piece of meat throughout the next few weeks it just reminded Haley of how badly she had treated the girl she had fallen in love with.

Also, her ass was killing her, the constant anal poundings leaving her poor little butt hole constantly aching and gaping wide open, making Haley avoid sitting down whenever possible, and struggling to hide the discomfort when she was forced too.

Which was why the first half a dozen times that Alex flirted, or attempted to flirt, with someone else Haley just ignored it, assuming that it was just part of her punishment. Also Alex was hopeless at trying to flirt, and it was really fun watching her fail so spectacularly, even after Haley had given her some pointers.

But as the week drew to a close another more enjoyable explanation popped into Haley's head. One she liked a lot better than the current explanation, although she avoided confronting Alex about it for an extra day as she was still trying to give her baby sister her revenge. Ultimately though she just couldn't resist, especially if it meant what she thought it did.

"Soooo, are you trying to make me jealous?" Haley asked after Alex once again struck out.

"Yes! God, how did it take you this long to notice?" Alex exclaimed, before a horrible thought came to mind, "You didn't think I was actually interested in those guys, did you? Cause I wasn't."

"I know." Haley smiled softly, "But you should totally keep it up. Keep people from wondering why your 'single', and it's so cute watching you try to play it cool. Because I love you sweetie, but you're anything but cool."

"Hey!" Alex frowned, and then grumbled, "So what, you will at least be jealous?"

Lowering her voice Haley whispered, "Are you kidding? I was going out of my mind."

Despite herself Alex smiled, "Really?"

Looking around to check no one was listening in Haley leaned in and whispered directly into Alex's ear, "Really... all I've wanted to do for the past few days is bend you over and fuck your big fat sexy ass in front of everybody. Or at least pull you into my arms and kiss you long and hard. You know, something to let these idiots know your taken."

"Haley..." Alex warned softly.

"I know, I know, we can't." Haley said softly, and pulled back slightly, "And I get it. I really do. I don't want everyone to know how much I love fucking my sister. Mostly because I don't want you to get away from me. But my question is, where you trying to make me jealous to punish me... or were you hoping that I remind you that you were mine in private."

Pulling back slightly so she look her sister in the eye Alex confessed, "I've loved topping you, but..."

"But?" Haley pushed.

Looking around to check no one was listening in Alex leaned in and whispered directly into Haley's ear, "I want you to take me home and pound my big fat ass until it's gaping wide open."

"Oh Alex..." Haley grinned, pulling back so she could look her sister in the eye, "All you had to do was ask."

*

They had gone to the maul for another date disguised as a shopping trip, so unfortunately it took quite a bit of time to get back home. Luckily it was the middle of the day and no one was home, so after briefly calling out to check Haley slammed her lips against Alex's and pushed the front door closed. Alex hesitated for a moment, and then kiss back, meaning that the next few minutes were a blur for the two Dunphy sisters.

The next thing they were really aware of was tearing off each other's clothes, Haley deliberately leaving Alex's booty hugging jeans to the end so she could enjoy the sight of that yummy ass being revealed.

Finally breaking the kiss Haley smacked that yummy ass as hard as she could and ordered, "Bend over!"

Knowing exactly what she wanted Alex smirked and crawled onto the bed and wiggled her big ass, along the way sarcastically murmuring, "Yes Mistress."

Haley didn't really hear what Alex said, and she didn't care as she was too busy drooling over the beautiful sight before her, eventually murmuring, "Fuck yeahhhhhh, that's definitely the position you belong in."

"Really?" Alex grinned, shaking her fat butt even more.

"Oh yeah." Haley murmured, crawling onto the bed and then grabbing that ass.

Honestly Haley wasn't sure if she said anything else. Probably, as she loved talking dirty, but it really didn't matter. What mattered was that she could squeeze and fondle Alex's amazing ass again now they were once again alone together, and more importantly she was back on top, and Haley took full advantage of that. Hell, it was probably minutes before she even bothered taking off Alex's jeans.

Although when she did Haley made sure to go slowly as possible so she could savour every bit of it, practically drooling as she revealed that beautiful thong covered booty. Then she grinned wickedly, grabbed hold of that underwear and pulled it up, almost making the fabric disappear in between those meaty cheeks.

"Hey!" Alex protested, "Cut it out!"

"What? You punished me when it was your turn on top." Haley pointed out.

"Yeah, but you asked me too." Alex counter argued while grimacing, "And it wasn't like this."

"I can't help it, this makes your fat ass look sooooooo gooooodddddddd!" Haley moaned, feeling like drool was literally coming out of her mouth at this point as she watched her sister's thong dig so deeply between her cheeks that it somehow made them look even bigger than normal. Then she grinned wickedly, "But if it's familiar punishment that you want..."

Alex then cried out joyfully as Haley roughly smacked her ass, making those juicy cheeks jiggle with the force of the impact and the sound of the blow echoing around the room.

Haley then of course repeated this process over and over again, although the next half a dozen spanks were more gentle and there was plenty of time between them, both sisters giggling as she did so.

Well, Alex was mostly crying out in a mixture of pain and pleasure as she received the kind of gentle spanking that she loved, and had so missed. It just made her feel so wonderfully naughty, especially as it was a prelude to nasty sister on sister fun.

She could have done without the wedgie though. It was so very childish, and painful and humiliating in a way that Alex didn't enjoy. At least not initially.

Then she started thinking about all the times Haley had done this to her when they were little kids. How long ago that felt. How they used to hate each other and really fight constantly. And despite how far they'd come, it was thrilling to be reminded of how they began.

Or more accurately Alex's earliest memories of them, Haley having confessed during one of their first times after sex that even back then it was clear how much smarter the younger sister was and the older one had found that threatening.

Those memories almost made Alex enjoy being wedgied, and looking back at the glee on her lover's face was enough to push it over the edge, because Alex would suffer through any indignity if it pleased her precious big sister.

Hell, she'd suffered indignities that she'd never even seriously thought she'd ever consider just for Haley's benefit, and once again Alex found that a submissive part of herself really, really got off on this latest humiliation.

Although she sighed in relief when Haley pulled the thong down, excitement then filling her body as Haley then pulled the thong and pants completely off of her, leaving her naked and ready for the real fun to begin.

Given Haley's track record Alex was shocked when her big sister didn't then immediately bury her face in her fat booty, although it seemed worth the wait as after one final smack Haley got off the bed, quickly retrieved her favourite strap-on and a bottle of lube and then quickly return to the bed.

Looking behind her and grinning Alex watched as Haley scrambled to get the cock around her waist, then she kneeled down behind the younger girl and grabbed hold of her ass again.

Alex was expecting her to spread those cheeks and start licking her butt hole, but again Haley surprised her, and again while Alex was reluctant and disappointed at first she quickly began to enjoy it, far more than what had come before.

Haley had considered just going straight to the rim job, but Alex's butt looked just so cute when it was discoloured, and it had been so long since Haley had given her little sister's big ass anything except a gentle spanking, and after weeks of her kid sister being on top and denying Haley her beautiful booty could there ever be a better excuse for a hard butt beating?

So that's exactly what Haley intended to give her baby sister. Honestly she had wanted to start it the second she pulled down that thong, if not sooner, but Haley had forced herself to give Alex little break before she really wanted that sweet behind of hers.

Now though she'd had her little break Alex was going to get the butt beating of a lifetime, Haley promised herself that. Well, she couldn't resist a little groping when she was back behind her sister, tooled up and ready to abuse her fat ass, Haley fondling those meaty cheeks for almost a full minute before she delivered a hard double smack which made Alex let out the most adorable a little squeak.

Haley then followed that up with a couple more doubles smacks before using just one hand to concentrate on one cheek and then the other, going back and forth as Alex cried out in a mixture of pleasure and pain which Haley so adored giving her kid sister.

"This is for all those ass fuckings!" Haley growled, delivering a particularly hard spank, and then repeating the process after she followed up with, "And this is for forgetting your place. And for making me love being your bitch. And for making me love you. For making me love this fat fucking ass! For making me addicted to fucking it. And spanking it. And licking it!"

She continued listing her little sister's sins as she brutally beat her butt, causing the meaty flesh to jiggle and bounce obscenely, and inevitably turn from the cute pink they had been after the first spanking to a dark and angry red.

It was easily one of the roughest spankings Haley had ever given Alex, and that was really saying something as Alex really loved abusing this big beautiful booty.

Of course this was not her favourite way to do that, and even though Alex never complained Haley could tell she was aching at this point for a different type of butt abuse, and as always Haley was only too eager to give it, which she did after the following words.

"And this is for making me want to stick my beautiful face up your fat fucking ass! Just! Like! This!" Haley yelled, emphasising the last four words with extra hard strikes before she shoved her face into her little sister's big ass.

For a second or two Haley just stayed there with her face surrounded either side by large cheek meat, before she began rubbing her face back and forth like she was motor-boating Alex's huge titties. After maybe a full minute of that she pulled the giant cheeks apart, spat on her favourite hole and then and only then did she start licking it.

She made up for lost time by really rubbing that spit in, pulling her head back a few times to repeat the process before she let go of the cheeks and then buried her face in between them again, this time while frantically licking her kid sister's forbidden hole and shoving her face so deep into Alex's ass that she was suffocating herself.

Alex had cooed and giggled when Haley had buried her face in her big booty and then motor-boated it, and then gasped and moaned when her big sister finally began the rim job.

Not that she hadn't enjoyed the spanking, because she did. A lot more than she would like to admit. Alex basically loved anything Haley did to her, and spanking would always hold a special place in her heart.

After all, they were being so very naughty, and while a gentle spanking was weirdly a celebration of that a brutal butt beating made Alex feel like she was getting the punishment she deserved for crossing such a forbidden line and putting her precious future in jeopardy with this incestuous affair.

Of course while a sadistic, or was it masochistic, part of her really enjoy getting her ass beaten it couldn't compare to the joy she felt whenever her big sister worshipped her ass. Or better yet fucked it.

Oh yes, Alex may like basically everything Haley had ever done to her since they started having sex, but nothing could ever compare to the joy of getting her fat ass fucked hard and deep by her loving big sister.

Alex was a total slut for it, and she seriously thought she would be even if it wasn't for the incredible orgasms which came at the end, or even the preparation she was receiving now, although she very much like that, especially whenever Haley literally shoved her tongue up her ass.

Back when Alex was getting butt fucked on a daily, and sometimes hourly, basis her big sister could easily shove her tongue as deep into her loosened butt hole as it could go, and they both particularly loved the really perverted times that Haley would stick her tongue into Alex's gaping ass hole and lick the battered and still stretched open walls of her rectum.

Now Haley couldn't get her tongue very far into Alex's ass at all, although on the bright side that meant she got fed up quickly and switched to fingers, Haley barely taking a moment to suck a couple of them before forcefully shoving one as deep as it would go into Alex's fat butt, the wonderful sensation of the anal penetration causing both sisters to let out a loud cry of pleasure.

"God sis, you've tightened up soooooo much the past few weeks." Haley moaned lustfully.

"Then loosen me up." Alex challenged with a wicked grin.

"Gladly." Haley purred, shoving another finger into Alex's ass.

That additional digit of course made Alex cry out, although there was a little pain mixed in with the pleasure that time. Recognising that Haley slowed her role somewhat, taking the time to gently pump those two fingers in and out nice and slowly, which initially Alex was grateful for.

In fact she smiled softly at her sister taking care of her. But it wasn't long before she got the impression that Haley was teasing her, although just as she was about to complain Haley picked up the pace ever so slightly and began twisting her fingers around inside her rectum to make sure it was extra ready for her big cock. Then Haley pulled those fingers out and suck them clean while using her other hand to slide the tip of the strap-on up and down Alex's butt crack.

After a few long seconds of that Haley quickly switched hands and then taunted, "You wanna get butt fucked by your big sister?"

"No." Alex grinned, "I don't want you to just fuck it, I want you to completely wreck it."

"Prove it." Haley pushed.

Looking back over her shoulder Alex gave Haley a look, then rolled her eyes, pressed her face against the bed sheets, reached back and pulled her ass cheeks as far apart as they would go. Then Alex started shamelessly begging, "Fuck me! Fuck my ass! Fuck my slutty little ass hole. Mmmmmm, come on sis, ass fuck me! Fuck your little sister in the ass. Fuck your little sister up her big fat ass and make her your bitch, just like she was before she took your tight little ass. Oooooooh yes, remind me who the real bitch who takes it up the ass is around here. Come on Haley, fuck me! Fuck my ass, ohhhhhhhh yessssssss, AH FUCK!"

Haley could have listened to Alex beg her to fuck her big butt for hours, especially when her little sister was spreading those meaty cheeks of hers and exposing Haley's favourite fuck hole.

However Alex's rectum had probably already tightened up after the fingering, and if she left it too long she might as well have not bothered, so even though she wanted to wait for longer it wasn't actually that long before Haley firmly pressed her dick against her baby sister's butt hole and began forcing it open.

As it had been awhile since she had last done this Haley took her time, both for Alex's benefit and her own, watching her kid sister's back hole slowly stretch for her until the anal ring was wide enough for her dildo to slip through and into Alex's ass.

Like with her fingers this anal penetration caused both sisters to let out a cry of pure pleasure, proving that even though it had been awhile since she had taken it up the ass Alex was still a shameless anal whore who needed regular butt fuckings like most people needed oxygen, and Haley promised herself she would never let either of them go so long without giving Alex's perfect ass what it so desperately needed again.

Especially after watching her cock sliding into that big fat ass, the fact that Alex was still spreading her cheeks and allowing Haley the perfect view of her baby sister's butt hole wrapped around her strap-on.

For what was probably a few minutes Haley continued to enjoy that sight, then it got even better when she started slowly pushing forwards, making inch after inch of that big cock slide into Alex's ass hole and deep into her rectum.

Unsurprisingly Alex continued moaning like the ass whore she was throughout, making Haley regret her decision to only use an 8 inch dildo. She should have definitely gone for the 12 incher, which had been both sisters favourite just before Haley let Alex turn the tables on her.

She almost considered taking the time to change now, but Haley couldn't stand the idea of pausing the sodomy right now, not right before, after or during the moment that her thighs came to rest against those meaty cheeks, announcing that her dick was buried in her baby sister's fat butt.

"God Alex, it's been way too long since I've been inside your fat ass!" Haley moaned softly.

"Too long." Alex moaned softly in agreement.

"But don't worry." Haley grinned, "You're never going to go this long without an ass fucking again."

"Yeahhhhhhh, please don't make me, oh fuck!" Alex gasped as Haley officially started sodomising her again, "Ohhhhhh yeahhhhhhhh, fuck me! Fuck my ass! Fuck my big fat slutty ass! Oh Haley, mmmmm, fuck me sis. That feels so good. Yessssssss, butt fuck me like a slut. Remind me how much I love it in the ass."

At first Haley was way too busy staring lustfully at watching her dildo sliding in and out of her kid sister's ass hole to even register Alex was saying anything.

Of course when she did she grinned wickedly, and even glanced up at her face briefly, before returning her gaze to where her dick was owning her younger sibling's shit hole as these wonderful words filled her mind.

The two sisters then continued like that for quite a while, the older one effortlessly loosening the younger one's rectum and preparing it for the pounding she fully intended to give her later. But as it turns out Alex was wonderfully impatient for it, giving Haley a wicked idea to punish her for it.

"Harder, pound my ass harder! Harder you bitch! Mmmmmm, I'm not some skinny weak bitch like you, my fat ass can take a deep hard pounding right the fuck now. So just do it. Fucking fuck my ass! Do it! HEY!" Alex's eyes went wide and horror as the big dildo was removed from her butt, the younger of the two siblings taking her hands of her cheeks, lifting herself up and looking around to protest, "Why'd you stop?"

"You were being a brat." Alex frowned, repositioning herself.

"No! No please Haley, I'm sorry if I was being a brat, just don't stop. Please don't stop fucking my ass." Alex pleaded shamelessly as Haley laid on the bed, "I need my ass fucked."