I fucked my sister's girlfriend while she watched

Let's get this straight - I've never been attracted to my sister. As siblings, we've been pretty close for years (it came naturally after our older brother moved out), but we've never had any interactions of that sort. Sure, I noticed her curves round out after her high school graduation, and no doubt she's acknowledged my muscles that developed after I started going to the gym, but it's been purely platonic, familial love between us. Which made it all the more surprising when she told me that her girlfriend wants to get pregnant, and they've decided that I should do the honors.

But before I get into the story, I should probably describe the people involved. If you'd like to skip this part and fill their faces in with your own fantasies, skip to the line further on!

First off, there's my sister's SO. For confidentiality reasons, I'll call her Haley. Quite self-assured, she holds the command in any room she's in (it doesn't help that she's just over 5'7"). She has DD, or maybe even DDD-size tits, the kind that are firm enough to keep their shape but soft enough to bounce with every step. She's had me in a choke-hold since the day I met her. She's also got a mind-blowing ass, but it doesn't make much of an appearance in this story. Haley's lesbian, but she was the obvious choice to carry the baby so that it'll look like a mix of both its parents.

Then there's my sister, Abigail. She's smaller than Haley, about 5'3", and much more approachable. About half of the boys in our high school liked her at some point, and she's always getting free drinks when we go to bars. We found out later that she has a strong preference for women, but that didn't stop her from getting around. That was until she met Haley at a concert a few years ago, and they basically fell into each others arms.

I, on the other hand, haven't been so lucky. Not that I haven't found women, I've had four or five steady girlfriends since I graduated college pre-pandemic. It's just that none of them lasted. My most recent relationship ended particularly painfully back in November, hence my hesitance to get back into the dating game. Looks-wise, I would say I've faired well. I'm 6'1", 180 lbs, and clean-shaven. I'm not one of those guys with shockingly-large dicks, but I've been complimented on my size quite a few times. Okay, now to the story.

It began when I received a text from my sister, who had recently left our hometown in Michigan to move to Harlem with her girlfriend. Their new house was a 45-minute drive from my apartment in Brooklyn, and they wanted to get dinner with me in Manhattan before heading to my place to see what I had done with it since they last visited. I said yes, thinking it was a nice way to welcome them into the city. But I would soon find out that was not why they wanted to see me.

I got to the restaurant a little early, so I was waiting for them at the table when they arrived. When they finally did, I was once again blown away by Haley. She wore a red dress with a neckline extending to almost beneath her breasts, showing off her entire cleavage. They both totally noticed my eyes drifting downwards as they were walking towards me. Abigail, on the other hand, wore a simple black dress with spaghetti straps that revealed a minor amount of cleavage, but I didn't notice that until later into the night.

"Dressed to impress, huh?" I joked.

"This is a fancy restaurant, Elliott. If anything, you're underdressed." Abigail replied coldly, glancing at my denim jacket and vintage t-shirt. I opened my mouth to throw a witty remark back at my sister, but Haley beat me to it.

"Hey, let's not start fights just yet. If we're going to live in the same city, you two should at least try to get along." She said, smiling, as she took a seat across from me. Abigail rolled her eyes and sat down next to her girlfriend.

After the entrées arrived and we had caught each other up on our lives, my sister set down her fork and knife, exchanged glances with Haley, and faced me nervously.

"Okay, so we haven't told many people yet, so don't go announcing it, but Haley and I...we'd like to have a baby."

"Damn, congratulations!" I responded.

Abigail took a breath. "We don't want to just have a baby though, we want to...have a baby." My confused expression gave away my thoughts.

"We know that most people like us usually adopt or get a donor, but we thought it'd be wonderful to actually have a baby that has a bit of both of us in it, don't you think?" Haley asked.

I looked at both of them before asking, "how-"

"We'd need the father to be someone with similar DNA to Abigail but who can actually, you know..."

My heart started beating faster.

"And we were thinking about doing this through a maternity clinic, but they do so many screenings and they have so many fees, we thought it'd just be easier to do it...ourselves." Abigail added. "Oh, and I wouldn't be in the room. Obviously."

Woah. I was just given the opportunity to fuck this beautiful woman, without any of the first date hassle and no strings attached. Ignoring the weirdness of the whole situation, it was the perfect one-night stand.

"It would be completely transactional, especially since I'm not even into your type." Haley said before taking a sip of her red wine.

"Ouch."

"Oh, come on Elliott, you know what she means."

Haley leaned forward, placing her elbows on the table. Intentional or not, I now had a perfect view of her tits, looking like they were begging me to agree. "So, are you interested?"

Without even having time to think about my response, the word "Yes" slipped out of my mouth. Haley lounged back into her chair and looked at Abigail, who was anxiously biting her lip while looking at her glass of wine. Haley looked back at me and thanked me.

"When would this happen?" I asked.

To my surprise, Abigail responded, "let's just get it over with tonight. If we wait any longer I'm gonna change my mind. And I can take a look at your place while you two..." She looked away from me and took a deep breath. Fortunately, a waiter walked by just at the right moment, breaking the tension. "Could we get the check, please?"

***

The cab to my building was silent. As I got to the front door, I looked over my shoulder and noticed my sister and her girlfriend still standing by the road, whispering. Haley gave my sister a quick hug, and I could just make out the words, "It'll be over before you know it."

When we got to my apartment on floor 3, I entered first, followed by the other two. I gestured to my couch and said, "You can chill here, Abby. Watch some TV if you'd like." Then I looked at Haley, who's gorgousness somehow caught me off guard again, even though I'd been with her all evening. "The bedroom's down this way. Should we just...go for it then?"

"Why not?"

"I pray to god this works the first time." Abigail remarked as she fell onto the couch.

Haley walked behind my sister to run her fingers through her girlfriend's hair. "I promise, I won't enjoy it one bit."

"Go on then. Don't take too long."

I walked Haley down the hallway to my bedroom and shut the door behind us, muffling the Friends theme playing from the living room TV. Haley sat down on the edge of the bed, taking of her heels. She then began to slowly remove each strap from her shoulders, until the top half of the dress fell to her knees, unveiling her perfect tits, held up by a black bra.

"What are you waiting for? Take off your pants." A subtle smirk creeped over her face.

"Right. Sorry." I unbuckled my belt, and lowered my pants to the floor. This is insane, I thought. My cock was obviously rock-hard, trapped beneath my boxers.

"Well at least we know it won't take long to get started," Haley snarked. I chuckled as I pulled my shirt up, my barely-visible abs tensed in nervousness. I thought I glimpsed a quick eyebrow raise from Haley once my t-shirt was off, but she turned away before I could confirm it. She finally removed the lower half of her dress, leaving her in only a pair of lace panties matching the bra. As she moved to the back of the bed, I dimmed the lights out of instinct.

"Interesting choice. It's almost like you're trying to make this enjoyable for me." The smirk returned. I tried to explain myself, but she just laughed and told me to chill out so we could finish quickly (no pun intended). I then climbed onto the bed and above Haley's gorgeous body. She let out a sigh of air, closed her eyes, and pulled her panties down, showing me her gaping pussy, ready to be fucked. "Let's get this over with."

I brought my boxers down to my knees, and rested the tip of my cock against her slit. Haley took in a big breath of air. "Should I?" I asked.

"Just put it in me, Elliott," she begged. There was a hint of pleading in her words, like she wanted this just as much as I did.

I slowly pushed into her, but we could both tell it wasn't going in smoothly. I hadn't considered that I might not make her as wet as she could be. Nevertheless, she moved one of her hands from the head of the bed down to her clit, and slowly began rubbing, eyes still closed. Her breathing began to get heavier as I felt her pussy slowly open up. Pushing further into Haley's lubricated pussy, my cock slid deep into her, and she gasped. I pulled out slightly, then pressed back into her, and I watched as her tits started to bounce. Building speed, Haley's breaths began to sound more like moans as she stimulated her clit faster and faster. Similarly, my breaths were speeding up as my balls slapped against Haley's ass with each thrust. Glancing up to her face, I noticed that her eyes had opened, and we were making direct eye contact as her eyebrows furrowed and she began to moan louder, and I began to push deeper, her tits still bouncing up and down like an earthquake. That's when I remembered that Abigail was still in the living room, and she could probably hear Haley's screams.

Maybe the TV will cover up the noise, I thought. But as I listened closer, I realized the show wasn't playing anymore. Before I could question it though, I felt Haley begin to shake around my cock, and she let out a long moan that could be heard throughout the building. She moved her hand away from her pussy, and, out of breath, asked, "how long left?"

"As long as I can see your tits bounce like that, it'll be done real soon."

"Here, let me try something." I slowed down my thrusting as Haley pulled my cock out of her dripping slit. She moved to sit on the side of the bed. "Lie down," she commanded. I turned to my back and laid my head on the pillow. Haley placed one of her legs over mine, and kneeled above my dick, her olive-colored breasts facing me. She lowered her pussy all the way on to my cock, and began to bounce. I was mesmerized by her massive tits, pulling on her waist to bring them closer to my face. "You like what you see?" Haley asked in a sultry voice, with her arms to either side of my head. I responded by shoving my face into her cleavage, licking her boobs all over, spending extra time on her nipples.

Suddenly, the door opens, and Abigail stands in the doorway, furious. "What the fuck? Whatever happened to 'I won't enjoy it'?" Startled, I take my face out of her girlfriend's tits, but Haley doesn't stop bouncing.

"Hold on Abby, he's almost done, stand out there for one more second!"

"I can't just wait outside while your fucking my brother, it was supposed to be quick!"

At this point, a sort of primal desire kicked in, erasing any ethical and social compasses I had. I know it's wrong. But I saw a need, and I had a solution.

"It would go faster if someone could jack me off while I'm inside her." I realized that what I had said was completely out of line the moment I said it. Maybe it was the heat. Or the dim lights. Or maybe it was the insanely sexy woman practically jumping on my cock as I was staring at her tits. I glanced over at my sister, who stood completely still, too surprised to speak. Trying to distract myself from my mistake, I just looked up at Haley, still leaning over me. While she was the most beautiful woman I had ever had sex with, it was true, I would need something else to finish me off at this point.

To my surprise, I heard Abigail step closer to the bed. She took a deep breath, then took a few more steps until she was right next to Haley and I. She could probably feel the heat radiating off of our bodies. It was so clearly wrong. Even so, I felt my sister's hand wrap around the base of my dick as Haley moved her pussy to the tip. Both girls started pumping my cock at the same time, as Haley's juices flowed over Abigail's hand. My breathing picked up. I stared into Haley's eyes as I felt her breasts touch my chest every time she lowered herself. Without thinking, I pushed my lips against hers, our mouths colliding as fireworks went off in my chest.

Tongues entangling, I opened my eyes and looked at my sister. She met my gaze, and I noticed a fire in her eyes that I hadn't seen before. We continued to watch each other as I made out with her girlfriend, feeling her hand move faster over my cock and Haley's pussy begin to tremble once more. Abigail then grabbed her own tits and squeezed them, the fire in her eyes only growing stronger. She began to pull the top of her dress down, the straps slipping off her shoulders, showing me her cleavage. I had never noticed how fucking hot my sister was before. Her tits spilled out of her dress, but my gaze stayed on her eyes. She then bit her lip while keeping her eyes locked on mine, and I felt cum pulse out of my cock into Haley's pussy. Everybody remained still for a few moments. Then Abigail let go, and pulled up her dress as Haley collapsed onto my body, her boobs against my chest.

"Come on, Haley. Let's go," my sister said while handing her girlfriend's clothes over. Haley reluctantly got up and off the bed and began to put her clothes on, with my cum beginning to drip down her leg.

As she and my sister started to leave the room, Haley looked back at me and said, "Thank you. You'll never believe what that meant to me."

"You don't have to leave so quickly, you know." I smiled, still catching my breath on the bed.

"We'll let you know what happens," Abigail said hastily as she held the door open for Haley. Once her girlfriend was out of the room, my sister took one moment to look back at me and we locked eyes again. The fire was still burning, brighter than ever. Then she shut the door.