What Happens In Mexico… My Busty Sister-In-Law

My wife, Julie, and I had been married for 3 years, but our sex life had slowed down to a standstill over the last half of those 3 years. Sex became a chore, and if we did summon the effort to fuck, it was very routine and mundane. We had basically become roommates and not much more. Needless to say, our marriage was on the verge of collapse.

Julie was short, with long brown hair, average build, but had packed on a few pounds over the last couple of years, which I assumed contributed to the fact that she never wanted to have sex anymore. I constantly told her she still looked great and tried to make advances, but she would always reject me or say "maybe later". After a while, I stopped trying.

Julie had a sister, 2 years younger, and her name was Callie. 3 years ago, when we met, she was a bigger gal herself, was very tall, about 5'10", had curly reddish brown hair, and while on the thicker side, she had a very warm smile, big eyes, and a beautiful face. About a year after I met her, she began doing Yoga and eating healthier, and in the last couple of years, she trimmed down and became a total smoke show. And while she lost so much weight, for whatever reason, she never lost any weight in her chest region; her breasts remained huge.

Callie and her boyfriend, Jeff, would often come over to our house for dinners and game nights, and we got along great with them. It was these occasions where Julie and I got along better, and we would have fun, forgetting about our troubles.

One of those nights, Callie and Julie got talking about the four of us going on a vacation together. I loved the idea, a nice break from the norm, thinking maybe Julie would even let me fuck her a few times if we were relaxed and on vacation. I got along well enough with Jeff, and I didn't object to the thought of hanging out with Callie at a pool or the beach either.

After some weeks of discussion and organizing, we decided on a quick 4-day weekend all-inclusive trip to a resort in Mexico.

When we arrived, we sort of did our own thing as couples, but would meet for dinners and during the day for drinks and such. They did a couple of excursions the first couple of days, while Julie and I just relaxed by the pool and the beach, in between naps. I tried several times to get Julie to have sex with me, and only after the second night did she give in. But once again, it felt like a chore, and she star-fished the whole way through. It was really stupid and frustrating.

The next morning, and our last full day there, I had had enough and decided we should hang out with Jeff and Callie the whole day, which Julie was fine with. So we initially met them for lunch and then would meet at the pool. Julie and I got there first and got 4 chairs, when I caught a glimpse of Callie and Jeff approaching us. Callie was in the most revealing white bikini I've ever seen. Thank god I had my sunglasses on, hiding my eyes, because they were scanning every inch of her body.

Back home, she always dressed very modest and reserved, even after she lost the weight. The most revealing things she would wear would be a tighter sweater or some lululemon sweatpants. Nothing like this white bikini. It shocked me. We all chatted for a while, and I found that with Callie, it was more effortless than back home for whatever reason, and she was laughing and joking around with me a lot more than we ever did back home.

After a while, we got tired of the pool and decided to make our way down to the beach, as the girls wanted to find seashells and such. I strategically timed it so I would walk right behind her. She had a white sheer dress over her body, but I still stared at her ass as we walked down the path to the beach. She was curvy in all the right places.

When we were on the beach, I feigned interest in picking up seashells with the girls, if only to keep checking out Callie. Even with Julia near, every time Callie would bend over to pick up seashells, I would take sneaky glances at her amazing cleavage. The white bikini top was working overtime to keep them contained. Despite the semi-cold water, my cock was chubbed the whole time.

I got cocky, though, on one occasion I was fairly close to Callie, and she bent over, grabbed a seashell from the water, and then raised it towards the sun to look at it, bending her back, which resulted in an amazing view of the front of her tits and stomach. Even with us both wearing sunglasses, I could tell she caught me. She gave me a funny look and a head tilt. I couldn't help but smile and quickly looked away. After a few seconds, though, I could tell she was still staring at me, so I had to look back, and then, quick-thinking, I gave her the same head tilt, pretending she was checking me out. She gave the cutest little smile, and I was relieved that she wasn't pissed and also a little turned on that she noticed me. We went back to picking seashells, and at the time, I didn't know if it was just in my head, but she seemed to be giving me more glimpses on purpose, going slower with her bending over, and even introducing unnecessary jiggling when she did.

When we were done, we all went to our rooms to get ready for dinner. Suffice to say, I jerked off furiously in the shower, thinking about Callie's big tits and the smile she gave me at the beach.

We met at dinner, and when Callie and Jeff walked in, I was once again stunned by Callie's outfit; she was once again dressed to the nines, all dolled up with makeup, wearing a bright neon pink bikini top under a loose-fitting black sheer top, a short tight black leather skirt and sexy 4-inch black stiletto sandal heels that make her seem 6 feet tall. Based on her reserved attire back home, I'm floored that she would even own such clothing, especially that leather skirt. We made eye contact as she sat down, but we didn't break it, and both smiled at each other, which intrigued me.

At dinner, we were all into the wine and having a nice chat, but I noticed Jeff and Callie barely acknowledged each other, which had me wondering if they were having one of their fights. Julie told me back home they would get into a ton of arguments and would make snide little comments to one another. It was our last night here, so I wanted everybody to have fun.

There was a dance club right on the resort, and I knew Julie liked dancing, so I suggested it to everybody. The girls were excited, but Jeff was being a wet blanket.

"Nahh, it's getting late and I don't want to be hungover for the flight tomorrow."

Callie gave Julie a look. "Well, I want to go dancing! Let's go!"

"C'mon, babe, let's head back to the room," Jeff weakly tried to convince Callie.

Callie coldly and sharply responded, "Not a fucking chance, it's my last night of vacation. You go".

Julie and I backed her up, agreeing with her and trying to convince Jeff to join us, but secretly I couldn't have care less if he joined. Callie didn't join in trying to convince him, which confirmed to me that they were fighting.

We finished our dinner and drinks and started to head to the dance club, and Jeff broke off and headed back to his room in a huff.

"Fuck him, god forbid we have fun on vacation," Callie said.

Julie hugged her, and we all walked to the dance club. When we arrived, I got three vodkas from the bar, and we sat at a cocktail table when the girls start clucking and chatting with each other over the loud music, and I began to think this might be a third-wheel mistake, as these two sisters could chit-chat for hours, and I'm sure they want to sister-vent about Callie's boyfriend.

Luck struck when a song Julie loved started to play, and she dragged us both out to the dance floor to dance. The booze has hit Julie, and I was reminded of the girl I married, as she got goofy and flirty and began to grind on me as we danced. I felt sort of bad for Callie, who was dancing off by herself beside us, when Julie grabbed her hand and brought her into our mini-dance circle.

A few moments after that, I was startled when Callie decided to dance closely on me as well, and at one point, both the girls started grinding on me, Julie on one side and Callie on the other. I didn't know quite what to think, but Julie either didn't notice Callie or didn't care. I got a nice feel of Callie's legs and thighs on my leg, which awakens my dick again.

More drinks flew into our gullets, and we were all pretty hammered. The dancing continued, and Callie seemed to be touching me a lot more, in front of Julie. No issues, surprisingly, so I decided to be a little bold as well and would go back and forth between grabbing Julie's hips and dancing and then doing the same to Callie. Julie often would be grinding in front of me, and Callie would go behind me, putting her arms around my neck, grinding me from behind with her boobs and body bouncing off my back and ass. I was having the time of my life. Callie had never even remotely touched me like that before. Back home, the only time we ever had physical contact was the occasional light hug at a family dinner.

I could tell Julie was starting to get horned up, and she whispered in my ear that she wanted to go back to the room, which I assumed was code for she wanted to fuck. It was a miracle.

I was excited at the thought of fucking Julie like old times and also felt horned up myself after dancing with these two sisters, so Julie went over and told Callie that it was time to leave. Callie was a little upset with Julie as she wanted to keep the night going, but she agreed to head back with us.

Callie and Jeff's room was about 4 doors down from ours, but when we got to Callie's room, she said she still wasn't ready for the night to end, and that she was just going to go to the private bar by our pool and have a few more drinks. Julie hugged her and said goodnight, and then I wandered over to hug Callie, and what occurred was definitely more than a standard family dinner hug. She squeezed me hard, pressing her big boobs against my chest, and she put her head on my shoulder. My hands wandered from her upper back to her lower back, just above her skirt and ass, before I squeezed her tightly enough where her lower torso felt the bulge of my dick in my pants. She didn't pull away, but I had to go fuck my wife even though I was captivated by what the hell was going on with her and me on this night. I was a little worried about Callie roaming the resort by herself, but she was a tough girl. I told her to be safe, and Julie grabbed my hand and pulled me into the room.

When we got into the room, Julie was a drunken mess and instantly grabbed me by the cock and dragged me over to our bed. She pulled my pants down and started sucking me off, but only for a minute. All of a sudden, she took me out of her mouth and then ran to the bathroom and started puking. QUITE the buzzkill to my erection, which instantly receded. I pulled up my pants and went to check if she was alright.

After she was done, I helped her to bed. Cockblocked by alcohol. FUCK. I was really annoyed, and even worse, I was also wide awake. I was starting to think about going out to the bar to drink with Callie some more, unsure if that was a smart idea or not. I decided to tell Julie and see her reaction.

"I'm not tired yet, I might go see if Callie is ok?"

Julie muttered, "Fine, have fun," and passed out.

I wondered if I shouldn't just jerk off in the bathroom again and head to bed, but ultimately I chose against that. To be honest, I wanted to keep flirting with Callie, I wanted to keep feeling alive, and to have fun. So I told myself, that would be the plan: go out and have a couple more drinks with Callie, some harmless flirting, then come back to the room, likely jerk off and fall asleep, and call it a night..

I left the room and hurried over to the private bar, both hoping and not hoping that Callie was still there. Sure enough, I see her at the bar, chatting with the bartender. Her long, sexy legs crossed, and that beautiful ass sitting on the barstool. I walked up to her and sat right beside her.

"I'm not done with this night either! SHOTS!" I surprised her, and she squealed and got off her stool and hugged me tight again.

"Oh my god, I'm so happy you came back!!! Where's Julie?"

"She's TKO, unfortunately."

"Oh no! Well, that's ok, just you and me then!"

At that point, I'm hoping it's not going to be weird that it's just her and me, one on one, as we've never hung out by ourselves before.

"I'm proud of my sister, the girl put away a lot of booze tonight! I haven't seen her that drunk in a long time. Tomorrow's flight is gonna be rough on her!"

"Probably us, too! Luckily, not for Jeff!" I said, sort of dickishly. But she laughed.

We both did two shots of tequila and continued the night. I was surprised how easy the conversation flowed; the booze obviously helped that along. But she was a completely different person from back home. I kept getting lost in her big, beautiful eyes and kept taking peeks down her black sheer top whenever she wasn't looking.

Some time passed before Callie brought up the dance club. "You know, I was having a really fun time dancing before. Jeff never takes me dancing or anywhere fun."

Suddenly, "The Plan" in my head changes. "Why don't we go back? I can still hear the music playing!"

Her eyes lit up and she squealed again.

"YAAAASSSSS!". She jumped up to her feet and grabbed me by the hand, leading me back to the path to the dance club.

Oops. This wasn't the plan. But fuck it! My heart started beating like a teenager on a first date holding her hand. We were both getting quite wobbly from the booze at that point, and with her heel sandals that she wasn't used to, Callie was stumbling and tripping all over herself. I was forced to save her from falling several times, but the best one was when I had to put my arm across the front of her chest to catch her, giving me a good little feel of her tits through her shirt, and all she would do was giggle. She seemed to enjoy my manhandling her back to her feet. I could feel my cock growing and batting around in my pants.

Against all odds, we finally arrived back at the dance floor and we started dancing immediately. With no Julie or Jeff there, she IMMEDIATELY went grinding her ass up on my dick, to which I happily let her feel my growing bulge. After a couple of times doing this, she had a confused look on her face.

"Hmm… I thought my sister would have taken care of this before you came back out?"

I nervously smile at her. "Ummm, she was a bit too focused on the toilet."

"Poor girl. And poor you!" she said, rubbing up against my dick.

The longer we danced with no consequences, the braver we got with exploring each other's bodies. I was forcibly grabbing her hips and forcing her butt on my dick, and she would return the favour by grabbing my hands and making me grab her waist, and a few times she'd move my hands down to her ass. I was getting too horny for words at that point; all I wanted to do was grab her big fucking tits and shove them in my face. But with people around, I had to behave. The best I could do was occasionally brush against them with my back and my chest. I would also lightly brush up against them, moving my hands from her shoulders to her waist. But I wanted more. And I could tell she did, too.

We ingested a few more drinks until eventually 3 AM hit and the dance club was shutting down for the night. I was exhausted but also a little nervous about where we would go from there. Everybody began to filter back to their rooms, and I could tell neither of us wanted to go back to our rooms yet. Side by side, arm in arm, we started wandering aimlessly around the resort. She reached for my hand and we held hands before we turned a corner, and Callie saw a public restroom.

"I have to pee. Wait for me out here?"

"Of course."

She leaned in and lightly pecked me on the lips before staring into my eyes for a few seconds. She smiled and started entering the ladies' room. She took a couple of steps inside, checking to see if anybody was in there, when suddenly she came rushing back at me, grabbed me by the hand, and dragged me into the public restroom.

We both know it's fucking go time.

The temptation finally snapped for both of us, and I grabbed her by the neck and laid a wet kiss on her thick lips while grabbing her ass. She returned the favour, and we passionately made out like teenagers for a good long while, moaning and gasping for air. I noticed there were 5 stalls in the restroom, so in case somebody came in, we could quickly jump in one for cover.

I grabbed her by the ass and squeezed it hard, lifted her up, as she wrapped her long legs around my waist. I placed her onto the sink counter and tore her black top over her head, revealing her massive tits barely held by a pink bikini top.

My first initial grope of them was heaven on earth. They were real and felt amazing. Callie lifted her arms behind her head and gave me a grin.

"I caught you staring at these on the beach, you bad boy."

"Can you blame me? They're fucking perfect."

I slid her pink bikini top under them and grabbed them, admittedly, probably too hard, and started caressing them and sucking them. I found myself like a wild animal, half biting, half sucking them, and making quite a mess with my saliva. Callie just moaned and giggled the whole time.

I pinched her nipples, gave them a little twist, and she had a surprised look on her face.

"I guess Jeff has never done that?"

"Jeff has no idea what to do with most things".

Callie then grabbed my head and shoved my face in the middle of them, smothering me.

After a few moments motorboating, she allowed me to come up for air and asked, "Why don't you take that hard cock out of your pants and fuck them?"

Music to my ears. She hopped off the counter, got on her knees, and enthusiastically unzipped my pants and dragged them to my ankles.

My fully erect cock snapped out, and she looked at it in awe. "I've been eyeing THIS all week!"

Instead of stuffing me between her tits, she spat on my cock, stroked me off for a bit, and then shoved me into her warm mouth instead. She sucked and licked me up and down, even attempted a couple of deep throats, which caused her to gag on my dick. Easily the best blowjob I have ever had. Strings and gobs of saliva fall onto her tits, and I had to focus hard not to blow my wad early.

When my cock and her tits were sufficiently wet, she took me out and shoved me between her big breasts. She wrapped them around my dick tightly, and bounced up and down with my cock peaking out of the top with every thrust. My cock was made for her titties, and she was a pro at using them. Going back and forth between titty fucking my dick and smacking it against her nipples. I would never have guessed this subdued girl I've known for years was such a freak. Jeff was a fucking idiot for not using this goddess properly.

"Wow, you're so hard. You must like slapping my boobs with your cock?"

My response was nothing more than a nod. I couldn't formulate a sentence. She just smiled and then stuck me back in her mouth.

She kept sucking me when all of a sudden, we heard a couple of footsteps outside. We went still for a moment, like deer caught in headlights, even though my cock is still in her mouth. We stared at the entrance, but luckily the footsteps faded. We started to laugh, as somebody would have had quite a sight had they chosen to come in. It was time to get back to business!

"Ok, now it's your turn," I told her. I wanted to taste that pussy.

I lifted her and put her ass back on the sink counter again. I spread her legs apart, slid her panties to the side, and started to make my way down her long legs, starting at her ankles, then kissing her thighs until I reached her warm, sweaty pussy. I shoved my tongue inside her as far as I could go, and she gasped.

I went back and forth between tonguing her and fingering her, and nibbling on her clit, much to her delight. I got a little worried when she started getting quite loud, but continued. After about 5-10 minutes of eating that delicious woman, she suddenly got super pissed off, surprised me by grabbing me by the face, and looked me right in the eyes.

"FUCK! If you don't stick your fucking cock in me RIGHT NOW, I'm going to fucking explode!"

Didn't have to tell me twice! I stood up, quickly removed her panties, and slid my rock-hard dick in her now-drenched pussy. She whimpered as I shoved my entire length into her. She put her long legs on my shoulders, and I began pumping her hard. Anybody walking by the ladies' room at that point surely would have heard us, but at that point, we didn't give a single fuck.

As if I wasn't already turned on enough, I had the amazing view of her perfect tits bouncing hard, almost hitting her chin with every thrust. I grabbed them both and accelerated my driving, squeezing her tits as they bounced wildly. I licked and sucked on her nipples while she grabbed the back of my hair and gripped it tightly.

We were both panting pretty heavily, and while pinching her nipples, I made out with her again; she shoved her tongue far down my throat, and we made out passionately as I continued to stuff her. I was getting close to nutting, so I took her off the counter, made her bend over with her elbows on the sink counter so I could fuck her standing-doggy style.

With her long legs and heels, she was the perfect height for this. I spread her legs a bit more and enjoyed the view of her pussy and asshole staring at me. I approached her from behind and slid back into her perfect pussy and started pumping away. I held her hips and railed on her to the point where she was screaming in delight.

After a few minutes, Callie told me she was gonna cum, and I felt her grip my dick and got even wetter as she cummed with me inside her. She muffled a scream and was panting for air. I gave her only a few moments to catch her breath before I started pumping again. The sound of her beautiful ass smacking against my body was echoing in the bathroom.

I was getting close, so I slapped her on the right ass cheek, reached around and squeezed her bouncing titties one last time, and started to jack-rabbit her from behind. Last minute, I caught a glimpse of me fucking my big-titted sister-in-law in the mirror, and that was it for me.

"Can I cum in your pussy?"

"Fuck yes, do it!"

I started exploding copious amounts of cum into her pussy. Halfway through, I took my dick out and laid a few remaining ropes on her ass cheeks. I was seeing stars and almost fell over. My balls were drained and ached immediately afterward.

We both caught our breath. I helped clean off her ass, and then she went into one of the toilet stalls to clean up the rest. She came out and gave a great big exhale, and instead of guilt or remorse, we both started laughing.

Callie tells me, "Can I be honest? I've wanted to do that with you for a long time," to which I had no fucking idea she felt that way.

We got our clothes back on as quickly as possible, and we walked back to our rooms. Even though it was like 4 in the morning, I didn't want the night to end. We reached Callie's room first, and I gave her a big hug, this time groping her ass, and she kissed me one final time and then went into her room. I did the same. What a crazy night.

The next morning, the four of us met for breakfast before our flight, all of us pretty hungover except for Jeff. Callie and I, apparently amazing actors, acted like nothing had happened. We barely looked at each other.

However, on the flight home, I caught eyes with Callie as she went to the back of the plane for the bathroom. She gave me a tongue flick and gave me a look that I couldn't resist smiling back.