The Social Experiment

But despite our inability to properly discuss it, things did change.

Over the rest of my time off for the holidays, Abby and I began to contact each other more frequently than we ever did.

We talked daily and spent almost every spare moment texting each other, and after a few nights of steamy phone sex and falling asleep while having tender, intimate conversation, I began to feel as if she really were my girlfriend.

Christmas came and went, then just like that, on new year's eve, I opened the door and was greeted to my absolute shock, by the girl who had been on my mind for every waking hour since our farewell a few weeks back.

"Abby? What the fuck?"

"Language, Caleb!" My mom called, and I grimaced as Abby grinned stupidly at me.

Abby leapt into my arms, and I spun her around, hugging her tightly as Mom and Dad came over to greet her.

"Well, look who finally remembered where her folks live," Dad muttered, but as our parents greeted her, I noted that our uncharacteristically exuberant greeting did not go unnoticed.

"You two seem happy to see each other. I thought you could barely stand each other for even one week a year," Mom muttered, and Abby and I quickly became flustered, wearing matching awkward grins.

We were like two kids caught red-handed, but to our relief, Mom didn't say anything more.

"I just thought it'd be a nice surprise to come home for our New Year's party," Abby muttered, and Dad smiled.

"Well, we're glad to have you, kid. Wait till you see the fireworks display tonight. Those Miller's won't know what hit them this year!"

Our family had a long tradition of hosting a New Year's Eve bash at midnight, inviting a lot of the neighbours and some family over, so most of the day was spent on getting everything ready for the night's festivities.

"Hey Caleb! Make sure you wear something nice tonight. We invited the Evans so Katie is probably gonna be here!" my Dad called suggestively, winking in my direction.

*Crash!

"W-who're the Evans?" Abby suddenly asked, toppling over a tray of sweets that Mom had just brought out of the kitchen.

"New neighbours," Dad called. "They moved here recently. They've taken quite the liking to Caleb ever since he helped them out with some car trouble, and that Katie is quite the looker. How come you've never offered to show her around town?" Dad asked, and I rolled my eyes.

"She's starting college in August anyway, Dad. Losing battle," I commented, and he smirked as he replied:

"Oh come on, you could always visit her like you do with Abby. Wha- are you okay?"

Abby suddenly started coughing loudly as if she was choking on something, and Dad quickly went over to check on her.

I eyed her curiously, but as the evening wore on our parents kept us pretty busy, scarcely giving us a moment alone.

At mom's insistence I ended up wearing some ridiculous shirt and a pair of dress pants, and to my surprise Abby wore a pretty yellow sundress.

As the guests started filtering in, Abby and I could finally relax a little, and get a moment or two to chat.

"You look amazing," I whispered to her, after we'd ushered in my Aunt Margaret and Uncle Steve.

They made a beeline for the alcoholic beverages, and Abby took the moment to pose for me, and I whistled appreciatively as she gave a little twirl.

"You know, if I knew you were this sexy I would have perved on you a lot more growing up," I whispered, and she swatted me playfully just as our cousin, Dannielle swept by.

It's like we're traversing a minefield! I thought with a sigh, and Abby leaned into me again.

"So who's this Katie?" she whispered, and I rubbed the back of my head nervously.

"Seriously, she's nobo-"

"Caleb!"

I nearly jumped out of my skin as my Dad suddenly called to me, and Abby leapt a foot clear of me, suddenly fidgeting with some fixtures on the entry hall mantle.

I scurried to the living room and my jaw dropped as I almost ran face first into Katie Evans.

"Oh- uh, hi," I muttered timidly, and she smiled back at me.

She was wearing an olive green dress with pretty frills, and her soft green eyes, brought out by the dark eyeliner she wore, were gazing invitingly at me.

"Hi," she offered timidly, giving a little wave, and I smiled awkwardly in response.

"Katie here has never been anywhere except the dining room and living room. Why don't you, uh, take her upstairs? Show her around?"

I rolled my eyes at my Dad's not so subtle hint, but even so, Katie merely smiled and offered me her right hand.

"Shall we?" she asked, and as I took her hand timidly, I heard a crash from the entryway.

"Shit!" Abby's voice called-

"Language, Abigail!" My Mom chastised her, and I shot an apologetic glance in her direction, biting my lip as I led Katie awkwardly from the living room to the second floor stairs.

"Your sister's a little klutzy," she noted.

"Uh, not usually. I think the long drive is just taking its toll on her," I muttered, and she smiled a little as we climbed the stairs.

"There's really not much up here," I muttered, "Our parents room is down that way, and mine and Abby's are down this hall. Although, there's a pretty nice view of the back porch from here," I offered, leading her to the windowsill where Dad had installed a little cushioned seating, giving a nice view of the backyard over the porch.

"Hm," she noted, as she accompanied me to the windowsill, before glancing at the room to my right.

"And, this room's yours?" she asked, and I nodded timidly.

"Uh- yeah, but I really haven't cleaned up-"

"I wanna see," she quipped, and I bit my lip nervously as she turned the knob, opening the door.

"Cozy," she commented, still smiling, and I chuckled nervously as I quickly slipped into the room behind her and turned the lights on.

I was quickly trying to clean up some of the clutter from my desk, when she came up behind me, and I gasped as I spun around, finding my face suddenly intoxicatingly close to hers.

She licked her lips, which were coated with a light peach coloured lipstick that gave her full lips a luscious allure, and her cheeks had that subtle tint of blush that made her already pretty visage seem that more inviting and attractive.

I breathed in slowly, trying hard not to make my discomfort apparent, and she smiled.

"You know, my parents seem really fond of you," she began, but as I made to reply, she continued:

"-but, I'm off to college in a few months and I don't really think I'll have time for a boyfriend."

"Oh, uh- that's... unfortunate," I muttered, but my relief was short lived, as she moved in closer to my face.

"The things is. You're kinda cute, and if my folks don't mind me hanging out here, then maybe we can have some fun before I head off to college?"

She stepped back, and held her hands together at her back and swivelled side to side with a girlish gait, straightening her back to accentuate the swells of her breasts and curves of her figure.

Her eyes were bright, and the attractive figure she cut was almost hypnotically alluring, but she was not my queen, and a little smile appeared on my lips as I began.

"Listen- uh, you seem really nice but-"

"There's someone else?" she asked, not missing a beat, and I nodded slowly.

"Hmn... if it helps, I'm good at keeping quiet," she offered suggestively, and I smiled a little before again shaking my head.

"I'm sorry."

"You're a good boy, Caleb," she muttered thoughtfully, heading for the door before turning back to add: "If your gal-pal ever falls through, maybe look me up?" she asked, and I rubbed my head as I gave a nervous chuckle, and she gave one more 'hm' before heading out.

I followed Katie downstairs, and she gave me a little wave before heading off to re-join her parents and the party out back.

I quickly scanned the house looking for Abby, when I finally noticed her standing on the far end of the veranda out back.

The lighting at the far end was pretty bad, leaving the spot in shadows most of the time, and I glanced about to make sure that everyone was otherwise occupied before stealing to her side.

"Just breathe, just breathe," she was whispering to herself, but despite the words I noted that her knuckles were white as her hands tightly gripped the wooden rails for dear life.

"Ah!" she shrieked, as I sneaked up behind her then wrapped my arms around her waist and held her tight.

"Something the matter?" I asked teasingly, and she quickly shook her head, though I could see the shimmering misty look of tears building up behind her eyes.

"No, no. I'm fine. Did you finish showing your 'guest' around?" she asked, and I chuckled.

"Well we did stop by the bedroom for a bit- ah!" I yelped as she stomped my foot, before turning on me, only for her expression to soften as she saw the teasing smile on my face.

"Did you really think that I would cheat on you?" I asked, and a tear ran down her cheek as she turned away from me again.

"I dunno what to think. This is confusing," she muttered, wiping at the tear before inhaling sharply, and I stepped closer to her and wrapped my arms about her once more.

"Then lets un-confuse it," I muttered, and she shuddered, placing a hand over mines.

"I'm your sister, not your girlfriend. I shouldn't feel this way."

"We shouldn't, but we feel the way we feel, don't we?" I asked, and she turned to study me a little, before sighing.

"We'll never be able to have children."

"Granted, children is a bad idea all things considered, but-"

"Our family will disown us," she continued.

"True, we will have to keep some things hidden-" I countered.

"Not to mention it's illegal where we live."

I sighed.

"Do you want to end things then?" I asked, and she quickly shook her head, more tears streaming down her face.

"Like I said," she muttered again, "confusing."

I took a deep breath, then turned her around to face me.

"Abigail Walker. You have been the beacon of light in the darkness that is my life. I've loved you more than I could possibly love anyone, and becoming intimate with you has been the single greatest joy I've experienced. I'd like to be by your side forever," I muttered, and as she smiled, wiping away her tears, a flustered laugh escaped her lips.

"Are you proposing to me?" she asked, and I shrugged.

"The whole marriage/proposal thing has kind of been lost on me for most of my years, so I don't know much about it. I'm merely expressing to you what I genuinely feel, so if that's what it is, I guess? Wha- hey!" I complained, as she punched me in the shoulder.

"Be more romantic about it then! You don't ask someone to be together forever then say 'I guess'," and I giggled at her imitation of my flat tone.

We laughed a bit, but as we settled down a serious expression re-appeared on my sister's face.

"It's only been a few weeks. What if you get tired of me?" Abby asked, and I flicked her forehead again in annoyance.

"A few weeks? I'm sorry, then who have I been related to all my life?"

"You know what I mean," she chided, and I chuckled a little.

"Well the honeymoon phase is bound to end at some point, but... do you really think you'll get tired of me?" I asked, and as she shook her head timidly, I shrugged.

"I don't either. So why not?"

"Because it could be hell. It's not always going to be flowers and roses like it was last week," she muttered, and I leaned in to hold her close once more.

"I don't expect it to be, but there's no girl on the planet that's worth the trouble more than you."

She blushed, risking a quick peck on the lips before taking my hand just as one of Dad's fireworks went off.

"It's close to midnight, isn't it?" She asked, a mischievous look on her face, and I quickly checked my phone before nodding.

"Fifteen minutes. What do you have in mind?"

She pulled me with her into the house, through the kitchen, down the corridor to the second floor stairway, and finally to the little perch nestled just outside my room.

As she plopped down on the couch, she pulled me down on top of her, and as she kissed me hungrily, I broke the kiss to cast a furtive glance down the corridor.

"A bit risky, no?" I asked, and she shrugged.

"Everyone's outside waiting on the fireworks display. Besides, ever since we started having sex I've been fantasizing about doing it right here."

I smiled.

This place was special to her, and to me as well.

We spent a lot of afternoons sprawled out here, basking in the warm glow of the afternoon sun while enjoying a light reading session, doing homework, or just chatting.

"Fine," I relented, knowing full well that the distraction outside was presenting us with a rare opportunity to make use of this special place.

She pulled me down on top of her, and started kissing me fervently, but as she began to struggle with the many buttons on my dress shirt, she sighed exasperatedly into my mouth mid-kiss.

"That thing looks ridiculous, by the way. If Mom ever makes you wear it again I'm burning down the house."

I glanced at it, then chuckled nervously.

"Can't argue there."

I helped her with the many difficult buttons and she tossed it, before helping me out of my pants.

She pushed me back down onto the cushioned seat, before climbing on top of me.

"I've been waiting all night for you to notice that I'm not wearing any panties," she whispered, a naughty look on her face, and she smiled as my throbbing erection pulsed under her at the revelation.

I slipped one of the straps of her sundress over her shoulder, and as the full luscious orb of her left breast came into view I felt her reach down and position my cock against her slit.

"You're already so wet," I noted, and she blushed, as she slowly rocked back and forth, coating my length with her dripping love juices.

"I dunno... there's something so dirty about being around Mom and Dad while wanting you to fuck me silly. I haven't been able to stop creaming myself all night."

My cock twitched against her again, and she smiled.

"Where's your phone?" she asked, and I quickly retrieved it from the pocket of my discarded dress pants.

"Six minutes," she noted, a playful look in her eyes; "Do you think we can make it?"

I chuckled, finally understanding what she was getting it.

We'd have a nice view of the fireworks from here after all.

It might be nice starting the New Year with some fireworks of our own.

She took a deep breath, as she rubbed along my length to the head, then exhaled slowly as she sank carefully onto my rigid rod.

"That really never gets old," she crooned, and I placed a hand on her leg, then moved it slowly up her leg, slipping beneath her dress to grasp her firm buttocks by the left cheek.

She leaned down to me, offering her exposed breast to my awaiting mouth, and I obliged, sucking it into my mouth hungrily as she began to rock her hips back and forth, stimulating my length deliciously within her tight inner embrace.

The pleasure of being inside of her again was borderline euphoric, forcing me to check myself if I was to last until the finale that she desired.

I glanced at the phone, lying on the seat beside us.

Two minutes.

I didn't need to worry about lasting much longer, but I needed to help Abby get closer and quick.

As she continued to ride me, slowly and rhythmically, I took one of her nipples between my teeth and tugged on it gently, and a soft, cooing sound slipped from her lips as I grasped and massaged the firm, toned flesh of her ass.

"Mmh, good baby brother. Suck my breast."

I was stimulating all of her favourite erogenous zones, but I knew that what got my sister off quickest was being made to feel like a wanton shameless slut.

I leaned back against the wooden ledge of the windowsill, and lifting my butt slightly off of the seating, I forced Abby to lean forward just a little more.

She moaned affirmatively, as the slight shift in position allowed her to achieve a deeper penetration, but that wasn't my main intention.

"They can see us from down there, you know. If anyone looks up now. Our parents, all of our guests; they'd see you riding her brother like a shameless wanton whore."

"Oh, Caleb. Yes! What kind of... slut... fucks her brother... shamelessly... in front of her family... like this. Unh!"

She panted the words, between moans and gasps, and as I glanced at the phone the time read '11:59.'

"Ten... nine... eight-!"

As countdown started outside, Abby began to ride me with reckless abandon, and I bit down into the soft fleshy meat of her breast as I surrendered myself to the blissful pleasure of delving deeply into my sister's forbidden womb.

"-Two... One-!"

"Unh! Mhn! Ahhhh!" she screamed out, an explosive orgasm tearing through her just as the first spurt of cum shot deep into her sacred place, and the explosive sounds of fireworks erupting outside drowned out our orgasmic cries, and the obscene sounds of our bodies smacking together in frenzied copulation.

I glanced briefly over the window at the fireworks display, then back to my sister who was studying me with a cheeky grin.

"Happy new year, Caleb," she muttered, and I returned the greeting before leaning in to share with her a belated New Year's kiss.

"Did you make a wish?" I asked, and she nodded, before blushing.

"Yeah, but I think some of it already came true."

I smiled as I leaned in, kissing her deeply again and wondering if our wishes, like our hearts, had indeed aligned.

Epilogue.

"Caleb, did you move my laptop bag again?"

"No, it's on the bathroom floor!"

I walked over to her room just as she emerged from the bathroom, blushing embarrassedly as she was caught with the bag in hand.

"What was it doing on the bathroom floor?" she asked incredulously, and I put a finger to my lips thoughtfully as I answered:

"Well... Somebody came home from classes while I was taking a shower, and demanded to be fucked immediately. Now I'm not going to point any names or call any fingers, but-"

"Oh my god shut up!"

"-she does answer to names like 'brother loving slut,' and 'shameless sister whore'- hey, ah!" I giggled as she tossed a towel at me while chasing me across the bedroom.

She caught me just around the corner of the bed, and as we tumbled to the floor, she panted, a devilish look appearing in her eyes.

"Oh no you don't. I have class in twenty minutes."

"So? Freshmen skip all the time."

"Oh? Isn't that's some good college advice from a part-time lecturer?! You know, coming to college after all this time was your idea."

"All this time? You worked a couple of years after high-school. Lots of people do that!"

I shot her a disapproving glance, and she reluctantly climbed off, but as she did a folder slipped from her laptop bag, and as she retrieved it, a mischievous grin appeared on her face again.

"Guess what this is~?" she teased in that typical sing-song way, and I eyed the folder curiously.

"What?"

"The applicants for the research project," she announced proudly, and I groaned, rolling my eyes in an exaggerated show of exasperation.

"I seriously cannot believe you actually found enough poor schmucks willing to trick their siblings like that."

"What? The money's good, and who knows. Maybe we might help an unsuspecting pair of siblings discover their 'true feelings' for each other? Huh?" she added, nudging me repeatedly while shooting me suggestive winks.

I let out a huge sigh, but as she smiled affectionately at me I couldn't help but smile back.

Truthfully, I knew there was little chance of it actually happening.

After all, the experiment had been repeated in the testing phase using Samantha's older brother, as well as a few other sibling pairs closely related to the research group, and none of the results were anything like what had happened in our own experiment, making our case a rare, and perhaps isolated instance.