My Girlfriend and I Have Sex in Front of Her Sister

Author’s Note: This story is heavily inspired by my other series, Exhibitionist Sister.

My name is Alex. It was a Friday night, and I was sitting in the basement of my girlfriend’s parents’ house. My girlfriend, whose name is Brittany, sat next to me on a couch to my left while her slightly-younger sister Melanie sat across from us on a different couch.

“Can you go get me a water bottle from the fridge?” Melanie asked.

“Me too, please,” Brittany said.

“What do I get in return?” I joked sarcastically.

As I was standing up, Melanie said, “I’ll flash you my tits!” She immediately turned red and started laughing hard.

Brittany just rolled her eyes and smirked.

“Oh really?” I said suspiciously. I was still speaking with a playful tone.

I gave Brittany a look. She just shrugged and nodded. To me, that meant she didn’t care

one way or another if Melanie flashed me her tits. And that didn’t really surprise me. Brittany

was fairly liberal when it came to nudity. Melanie looked at Brittany, who gave her sister the same shrug and look that she had given me.

“I was joking,” Melanie said hesitantly. “But if that’s what I have to do, then I’d do it. They’re just tits.”

I turned and faced her, crossing my arms. “Just tits, huh?” Brittany has lovely boobs — big and round with perfect nipples. I could tell that Melanie’s were big too, but obviously I’d never had the fortune of seeing them in anything less than a swimsuit.

“Yeah,” Melanie shrugged. “So do we have a deal?”

I briefly glanced back at Brittany, who just shrugged and nodded again.

“Yes, we have a deal,” I said, trying to sound confident.

“Do you wanna see now or when you get back?” Melanie asked.

“Money up front,” I said, causing both Brittany and Melanie to laugh.

“Fair enough,” Melanie said. She grabbed the bottom of her shirt and pulled it up slowly, hooking her fingers into her bra on the way up. She quickly pulled both her shirt and her bra the rest of the way up, revealing to her sister and I her tits.

“Holy shit,” I said. They were big — about the same size as Brittany’s. Both girls had cute nipples — not too big, not too small. Melanie’s were very obviously hard. Perhaps she was getting a kick out of showing herself off? After all, she certainly had something worth showing off, that’s for damn sure.

“Goddamn Melanie,” Brittany said, nodding with approval. “You’ve got a nice rack.”

“Thanks sis,” Melanie said with a smile. She held her shirt and bra up for a while, giving me a good look. I was definitely committing this to memory for the next time I jacked off.

“Have you gotten your fill yet, Alex?” she asked me, still smiling and blushing. Her tits were surprisingly perky given their size. I would’ve loved to squeeze them, but that wasn’t part of the deal. Honestly, just the fact that I was ogling my girlfriend’s sister’s tits was downright shocking.

“I could look at your tits all night,” I said, sighing. Perhaps that was a bit much, but I really don’t think it was too out of line. I mean, Melanie flashed me her tits, and Brittany had given permission after all. “But I suppose you’ve now held up your end of the deal. You have really nice boobs, Melanie.”

“Thank you,” she said cheerfully. She pulled her bra and shirt back down, adjusting them slightly as she did so.

I quickly turned and went to grab waters — I was just gonna grab one for everybody. By the time I got to the fridge, my dick was fully erect. I sighed. There was no use in trying to get rid of my boner unless I jerked off, and I wasn’t gonna do that right now. If Melanie could show me her tits, then she could handle the fact that I had a boner. Besides, she’d only see the tent in my pants, not my actual dick.

I walked back with the bottles of water in hand. As soon as I came into view, Melanie began to giggle. Brittany looked back towards me and cracked a smile.

“Jesus Christ, Alex,” Brittnay laughed.

“What?” I said, shrugging. “Did you guys not expect this?”

“Well, I did,” Brittnay giggled. “I don’t know if you did though, Melanie.”

Melanie was blushing. “That’s from me?”

“What else could it be from?” I asked, handing Brittnay her water bottle and then Melanie hers.

“I don’t know. Good point,” she said, giggling. “That’s very flattering.”

“I wasn’t lying when I said you have gorgeous tits.”

“Thank you,” she blushed.

I sat down next to Brittnay, making no effort to conceal my erection. My dick was angled down my left leg, but it was trying its damnedest to free itself from my pants. That is to say the tent was quite large. My dick was above average — maybe a hair under 6.5” — and I was relatively thick too.

Melanie was trying not to stare, but she was fairly unsuccessful in this endeavor.

Brittany smiled and rolled her eyes. “Just look at it if you want to look at it,” she said, laughing. “You aren’t fooling anybody.”

“Okay,” Melanie blushed. “I just didn’t know if you’d care.”

“I don’t,” Brittany said, still laughing.

“It looks big,” Melanie said bashfully. “Is it?”

“Just about six-and-a-half inches,” I shrugged. “Which is above average so yes, technically.”

“He’s pretty thick too,” Brittany grinned. She could tell that her sister was dying to see my dick, and my liberal-when-it-comes-to-nudity girlfriend apparently didn’t see the harm in letting Melanie get what she wanted. “Y’know, Alex, if it’s uncomfortable being so hard in your jeans, feel free to, you know, make yourself more comfortable. Plus I can tell Melanie here is itching to see it.”

Melanie inhaled sharply — probably in anticipation of potentially seeing my erect dick, and then giggled, presumably from embarrassment.

“Good God, Melanie” Brittany said, laughing. “You must really need to get laid or something.”

“I mean, yeah, kinda,” Melanie said sheepishly. Brittany just smiled and rolled her eyes.

“Are you sure?” I asked Brittany. I had no problem taking my hard cock out right now, but I didn’t want this to cause problems. Melanie was Brittany’s younger sister, after all.

“Yeah, who cares?” Brittany shrugged.

“Alright,” I said. I stood up and unbuttoned my jeans. I unzipped them and pulled them down, kicking them off my feet. There was now just a big tent in my boxer briefs, which did significantly less to conceal the exact anatomy of my very hard dick.

“Wow,” Melanie said softly. She could definitely see the outline of my cockhead pressed against the fabric of my boxer briefs. I could tell this only made her desire to see the real thing more intense.

I looked at Brittany one last time, who once again smiled and nodded. I hooked my thumbs into the waistband of my boxer briefs and pulled them down, springing my erection free. It swung out and up, bobbing up and down a little before coming to a rest pointing straight forward.

Melanie stared at it hungrily.

“See?” Brittnay said. “He’s got a big dick.”

I turned to the side a bit, causing my dick to once again bounce back and forth. I was showing Melanie a view from the side with my balls hanging down below my dick. I was lucky to have shaved yesterday. My ballsack was hairless and the rest of my pubes looked very well-maintained. I’ll admit it didn’t always look like this, but it did now and that’s what counts. I looked at Melanie’s face and I could tell she was loving the little show I was giving her — letting her see my hard dick from a bunch of angles.

“Yeah,” Melanie said slowly. “It’s so big. Wow…”

I sat back down; my dick now pointed more up towards the ceiling. I made sure to keep my legs spread so Melanie had a good view of it. There was a small dollop of precum oozing out of the head. I spread my arms out along the back of the couch. My right leg was way out to the side while my left leg was draped over Brittany’s legs, giving Melanie a completely unobscured shot of my cock and balls.

“Don’t you just love how shaved ballsacks look?” Brittany asked. She reached over and cradled my sack in her hand briefly before letting it go.

“Mhmm,” Melanie said. “I always just want to put them in my mouth.”

“Exactly!” Brittany grinned.

We continued to talk for a bit — mostly about work, school, friends — just random things. The entire time I was full-mast and Melanie was mostly just looking at my dick. Being exposed in front of my girlfriend’s little sister — especially after she flashed me her tits — was driving me crazy.

After about five minutes, Brittany reached over and, without looking, took hold of my shaft with her right hand. She was the one talking at this point, which was good because otherwise the conversation would’ve abruptly paused. She began to slowly stroke it up and down without really acknowledging what she was doing. When her hand was at the top, she made sure to spread the precum around my cock so she could stroke me slightly faster, which felt really nice. Melanie was now just completely staring at my dick, drinking in the sight of the handjob I was receiving. I was in heaven — being as hard as I was for this long with no action was beginning to really drive me nuts.

A moment later, Brittany let go of my shaft. Melanie didn’t do much to hide the disappointment on her face, but that look vanished when she saw Brittany putting her hair in a ponytail.

No way, I thought. She’s not about to suck my dick right now, is she?

Melanie was talking about work. She continued to speak, but her voice slowed and stuttered as she watched Brittany sit up a bit, shifting so that she was sitting on her knees.

“I’m listening,” Brittany said. She turned towards me and bent down. Time almost moved in slow motion as she began to trace her tongue up and down the length of my shaft. She held my ballsack with her left hand, massaging it very gently. She was doing her best to not obstruct the line of sight between my cock and Melanie.

Melanie continued to talk, albeit she was struggling with words a bit. Brittnay traced her tongue up my shaft and began circling the head. Melanie inhaled sharply again. Brittnay slowly took the head of my cock into her mouth, still massaging my balls. Her lips krept down my shaft, taking more and more of me into her throat. Once she was almost all the way down, she let her head drift back up. Melanie watched the rest of my cock emerge from her big sister’s throat. With that, Brittnay began to bob her head up and down — going about halfway down my cock each time, her mouth opened wide to handle the girth of my dick. With her free hand she began to pump the base of my shaft. She wasn’t really able to talk so Melanie and I continued the conversation — which was about how Melanie’s boss was being passive aggressive towards her and a few other employees — while Brittany blew me. I figured Brittany would keep going until I came.

“Well,” I said, struggling to keep a level voice as I got my cock sucked. “I’m sorry your boss is being such an asshole.”

“Yeah, I don’t know,” Melanie said slowly. Again, she was basically just staring at my cock disappearing into her sister’s mouth. “It’s annoying, but I’ll live.”

“Right,” I said. We had to speak up a little bit to talk over the sounds of Brittany slurping and sucking my cock. There was a lot of wet smacking and slurping as her lips and hand ran up and down my shaft. “At least you’re not in this alone, so to speak.” At this point, I couldn’t help but moan quietly when I wasn’t talking. I could tell this was driving Melanie wild — I guess she liked hearing guys moan in pleasure.

After another minute of sucking my cock, Brittany came up off of it. She stood up and stepped in front of me, gesturing for me to lay down. I did as I was instructed, laying down on my back on the couch. My cock pointed straight up towards the ceiling. Brittany was wearing a pair of girl running shorts which she quickly pulled down and tossed atop my jeans. She got on top of me, straddling my cock. She reached down and pulled her panties to the side before mounting me, aligning my cock with her sex. Slowly Brittany sank onto me, taking my erection side her pussy while her sister watched us from three feet away. Nobody was really talking. Once I bottomed out inside Brittany, she began to ride me. She was moving slowly, probably because any faster and she risked having me unload inside her sooner than she would’ve liked. She got herself into a good rhythm, bouncing her ass on my cock, moaning softly as she rode me.

Brittany picked up the conversation where Melanie and I had left it, resuming the discussion about Melanie’s boss at her job. The three of us continued to talk, all the while Brittany was riding my cock up and down. Her pussy was incredibly wet, and the sound of her pussy sliding up and down my cock was quite loud. Brittany and I struggled a bit to talk — there were a lot of moans and grunts intermingled with our words. Melanie was also struggling; I’m pretty sure her head was spinning from a mix of shock and horniness. In fact, I could tell Melanie was incredibly turned on — beyond the fact that she was having trouble speaking normally. She was completely flushed, breathing hard, and her nipples were poking through her top.

Brittany bounced on my dick for a little longer, her moans grew more intense as time went on. Then, she sat up straight, reached down, and pulled off her top. She was wearing a lacy red bra underneath. She reached back and unhooked that, throwing both her shirt and bra onto the growing pile of clothes on the floor. Now she was wearing nothing but the pair of panties she had on, which were of course pulled to the side. She resumed riding me, this time moving in a more up-and-down motion. The point of this was obvious — she was trying to make her tits bounce as we fucked each other. And her plan worked. I matched her movements, thrusting up into her as she came down onto me, causing her boobs to bounce wildly as my cock entered and exited her. I figured it wasn’t super comfortable for Brittany, but it sure did look good. I could see Melanie’s eyes darting between her sister’s ass and her sister’s tits.

A moment later, Brittnay let my cock slide out of her. She stood up and walked over to the foot rest, pulling it in front of the couch we were sitting on. The foot rest was just like a mini square version of the couch. She gestured for me to lay down across that such that I was perpendicular to the couch. I did so, meaning my feet were pointed towards Melanie. Brittany climbed back on top of me, this time leaning forward a decent amount. She braced herself against my chest with one hand as she reached back with the other, aligning my cock with her pussy. She was giving Melanie one hell of a fuckin’ view.

Melanie watched as her sister slowly sank back down onto my cock. Melanie could see everything. She could see Brittany’s tight little asshole, Brittany’s wet pussy, and my cock and balls perfectly. Brittany began to bounce her ass up and down again, riding my cock hard and fast. I matched her momentum as best I could, fucking her back. It must’ve looked incredible from Melanie’s perspective — to actually see my cock sliding in and out of her sister’s warm, wet pussy. To watch her sister’s ass cheeks bounce up and down with Brittany’s little brown asshole peeking out from in between them. She could see my balls bouncing with each thrust. Honestly I don’t know how she kept herself from masturbating to this.

“I can’t last too much longer,” I said in a hushed tone to Brittany, who had given up on holding in her moans. In fact, the room was basically filled with Brittany’s cries of pleasure, our bodies slamming together, and the wetness of her pussy and my cock.

With that, Brittany sat all the way back up. She let my cock slide out of her pussy, and at once I knew what was happening. Brittney reached back and held my dick in place, lining up her asshole with my swollen cockhead. I heard Melanie say something like “Oh my God” as Brittnay sat herself down onto my cock. There was some resistance at first, but Brittany’s asshole gave way and slowly my cock entered her final hole. She groaned loudly as she lowered her body all the way down until I was completely buried in her asshole. Brittany began to ride me again, moaning even louder this time. I held onto her hips and let her do most of the work initially.

From Melanie’s perspective, she saw Brittany’s ass cheeks bouncing up and down as my throbbing cock stretched her asshole. As Brittany began to fuck me harder and faster, I matched her pace, thrusting into her gently as she rode me. Her ass milked my cock — the feeling of her tight little asshole sliding up and down my shaft was incredible. The fact that Brittany’s little sister was watching my cock disappear into that tight little asshole was fucking intoxicating.

I knew I had the “green light” to come whenever, so I just let myself go, enjoying the experience. The fact that I was fucking my girlfriend in the ass right in front of her little sister was unmatched, and I was only able to last about two minutes before I tensed up and I felt the familiar tightness in my balls. I knew that I had hit the point of no return.

“I’m gonna come,” I grunted, loud enough for Melanie to definitely hear me. I wanted her to know I was pumping a load into her sister’s asshole.

Brittany picked up the pace slightly. I arched my back, and I felt my toes curl as I began to ejaculate inside Brittany.

She and I both moaned loudly as the first rope of cum erupted out of my cock and into her ass. I heard Melanie say something like “Oh my God, holy fucking shit.” I moaned loudly and shot another three ropes inside of Brittney’s butt. I hadn’t come this hard in ages.

I was so turned on that Melanie was watching me empty my balls into her sister’s bowels. Britteny was still riding me, coaxing every last drop of cum from my cock. Finally, my orgasm finished. Brittney slowly leaned forward, letting my dick slide out of her ass. Once I was out, she shifted back into position but stayed put, letting Melanie get a good look at her punished little asshole with my cum dripping out of it.

A moment later, Brittney got up. She quickly went to the bathroom to clean up, leaving me and Melonie alone together. I sat up, looking at Melanie, who gave me a smile and a look that spoke for itself. I returned her smile. I didn’t really know what to say, but it wasn’t at all awkward. We both just sat there, sharing a surprisingly comfortable silence (aside from my heavy breathing) until Brittney came back.

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