My Sister-in-Law Took Me to a Hidden Beach

That summer, I started seeing Mara almost every day. She was Darío’s sister-in-law, my business partner and friend for years, and she ended up slipping into my routine with a dangerous ease: mornings at the beach, long dinners, drinks on terraces along the promenade, and those jokes loaded with venom that only seem innocent as long as nobody makes the first move.

Mara had been separated for some time and carried that reputation of an inaccessible woman that makes everything one imagines feel dirtier. She had two daughters who were already adults, a quick tongue for answering any jab, and a way of looking at you when she smiled that made it clear she knew exactly what she provoked. She never showed off, and perhaps that was why we all looked at her more than we should.

I was carrying my own contradictions too. I was married, had an orderly life, a comfortable routine, and the kind of marriage that looks stable from the outside even though it had been without fire for years on the inside. I got along well with Mara from the start, without awkwardness or strange silences. We treated each other with confidence and a touch of cheekiness, and that was precisely what got me into trouble.

The night before it all happened, we had arranged to have a drink after dinner. My wife decided to stay home because she had a headache, and I went down alone to the harbor terrace where Darío, his wife, and Mara were already waiting. The moment she saw me arrive, she stood up, kissed me on both cheeks, and slowly squeezed my arm.

—That shirt suits you far too well —she said, without quite moving away.

—Don’t tease me tonight —I replied with a laugh—. I’m feeling sensitive, and on top of that I’m unsupervised.

The table erupted in laughter. Her sister even let out a “Take advantage, he’s flying solo tonight,” and the joke hung in the air a second too long. Mara said nothing, but held my gaze with a half-smile that was no longer a joke.

The next day, we organized a dinner at a rocky cove away from the center of town. Several of us went: families, coolers, meat for the grill, beers, low music, and children running around on their own. Everything was normal until we saw a breathalyzer checkpoint set up at the roundabout on the way out, just a few yards away. We thought they would leave before us. They didn’t.

The hours passed and the patrol was still there. We kept drinking, grilling meat, and stretching out the night with that false patience of people who know they can’t leave yet. Around midnight, we were all uncomfortable, waiting without wanting to look as though we were waiting. I stepped away with a cigarette and started walking along the shore, following the dunes until I lost sight of the group.

I sat on a flat rock, with the dark sea in front of me and the distant murmur of the gathering behind me. The air smelled of salt, dying embers, and summer. I thought I’d go back in a few minutes, but then I heard footsteps sinking into the sand.

It was Mara.

She approached unhurriedly and sat down below me, resting her back against the rock where I was sitting. Her arms lay across my knees as if that gesture had always belonged to her. For a while, neither of us said anything. We only watched the moon’s reflection on the water.

When a distant voice sounded from the other side of the dunes, I made as if to stand. Mara tilted her head back to look at me and, in that same movement, pressed my crotch with the back of her head. It was a clear, calculated touch, impossible to mistake.

—Let the others clean up —she murmured—. You’ve done enough work already.

Before I could react, she took my hands and brought them to her breasts, over her bikini. Her tits were small and firm, and her nipples were already hard beneath the fabric. She began moving her head slowly, rubbing herself against my bulge with an obscene, tranquil provocation, as if she had been thinking about that moment for hours.

—Put them inside —she said. —Don’t make me ask twice.

I felt a hard thump in my chest. Desire, surprise, fear that someone might appear. All of it at once. I slipped my hands beneath the bikini top and grabbed her tits. Her nipples were long, tense, genuinely sensitive. I had barely brushed them between my fingers when she let out a low moan. Then her hand slid inside her panties and she began touching herself in front of me.

I heard her breathing grow faster. At first I pinched her nipples carefully, then more firmly, watching her arch her neck and squeeze her thighs together. She fingered herself hungrily, getting wetter and wetter, while her head kept pushing my cock through my swim trunks.

—That’s it… don’t stop —she whispered—. Pull them.

I obeyed. I tugged her nipples a little harder and her whole body shuddered. Her hand moved at top speed between her legs, her breathing became ragged, and she dug her fingers into my knee. She came like that, biting her lip so she wouldn’t moan loudly, trembling against the rock while I kept squeezing her tits.

When she had recovered some of her breath, she turned onto her knees in front of me. She reached through the leg of my swim trunks, pulled out my cock, and held it for a moment as though she wanted to look at it before using it. Then she ran her tongue from the base to the tip, slowly and wetly, without taking her eyes off my face.

—Fuck… —escaped me.

She didn’t smile. She shoved it into her mouth in one movement, as far as she could, and began sucking me with a determination that disarmed me. I was too hot, too surprised, and besides, it had been a long time since anyone had sucked me like that. I gripped the rock, trying to hold out, while she licked my glans, sucked me hard, and massaged my balls with her hand.

I lasted no time at all. I warned her through clenched teeth, but she didn’t pull away. On the contrary, she took me deeper and made me come in her mouth. I swallowed hard and closed my eyes when I felt my orgasm pulsing out. She swallowed it all without taking my cock out until the very end, as if that was exactly what she had been waiting for.

When she finished, she kissed the tip and wiped the corner of her mouth with her thumb.

—Tomorrow morning, you’re coming with me —she said—. Make up any excuse. I want you to fuck me for real.

I didn’t answer right away. I didn’t have to. We both knew it was already done.

***

Half an hour later, with everyone in front of us, I mentioned that the next day I had to go to the neighboring town to look at a few things for the house. Mara immediately asked if she could come, saying she wanted to stop by a store before it got crowded. It sounded so natural that nobody suspected anything. Not even my wife, who never got up early on vacation.

I picked Mara up the next morning at around nine. She got into the car wearing a beach dress open from top to bottom, barely tied at the waist, with a pink bikini underneath that emphasized her tanned skin. She shut the door, grabbed me by the nape, and kissed me, sliding her tongue into my mouth until she left me breathless.

While she kissed me, she slipped her hand onto my thigh and squeezed my cock through my swim trunks.

—Start driving —she said. —I’m not going to waste the morning talking.

I left town as best I could with her pressed against me. She slipped her hand beneath my shirt and began playing with my nipples. They had always been one of my weak spots, and that bitch had discovered it in a single night. She pinched them with her nails, gently at first and then hard, watching my breath catch.

—If you keep this up, I’m stopping right here —I warned her.

—Then stop —she replied, twisting one until I let out a curse.

I took a secondary road along the coast and went down a dirt track to a grove sunk below road level. The car couldn’t be seen from above. I stopped the engine and turned toward her. Mara was already taking off her dress with obscene haste.

—Everything off —I ordered.

She took off her bikini without playing shy. I opened the car’s sunroof and she stood on the passenger seat with her back to me. She planted one foot higher, spread her legs, and showed me her open pussy, shiny and swollen with desire. Her slit was soaked, and a thin trickle of fluid ran down toward her ass.

I leaned in and ran my tongue over her buttocks before moving down to her pussy. I spread her lips with my fingers and licked her from bottom to top, burying my tongue while she gripped the roof and began to moan. She didn’t need much warming up. She had been ready since she got into the car.

I pushed two fingers inside her and they slid in without resistance. Then three. She writhed, pushing her ass toward my hand.

—Deeper —she panted—. Get them all the way in.

I obeyed. I fucked her with my fingers while sucking her clitoris and pressing her asshole with my thumb. I felt her clench around my hand, felt her legs tremble. As soon as I pinched her clitoris between two fingers, she came with a sharp spasm, squeezing her thighs together and letting out a hoarse moan she had to swallow.

I pulled out my soaked hand and brought it to my mouth. She looked at me over her shoulder, her face flushed.

—Now fuck me —she said. —No looking at me. Fuck me.

We got out of the car and I pressed her against the hot bodywork. I spread her legs with my foot, pulled out my cock, and found her from behind. I entered in a single thrust, without gentleness, and the sound of her moan disappeared among the trees. She was so wet that the penetration was direct, deep, filthy.

I grabbed one breast with one hand and held her hip with the other to set the pace. I began fucking her hard, driving into her all the way, pulling out and thrusting in with dry blows that made the car vibrate. Mara spread her legs wider to take me better and pushed her ass back, asking for more without needing words.

—That’s it, you bastard… that’s it —she panted—. Don’t slow down.

I pinched her nipples hard and she let out a muffled cry. She liked pain right at the limit. I tugged them again while fucking her faster and faster. The wet sound of my cock entering and leaving her mixed with her broken breathing and the slap of her hands against the metal.

—Don’t come inside me —she said between pants. —Don’t even think about it.

I hadn’t planned to do it there. I pulled out, stroked her swollen pussy, and brought the tip to her ass. She understood at once. She reached underneath, grabbed my cock, and positioned it at her entrance herself, spreading her buttocks with her other hand.

—Slowly at first —she murmured—. Then give me whatever you want.

The tip entered with some resistance, helped by her own wetness and a little saliva. I pressed forward calmly, feeling her anus yield millimeter by millimeter until it swallowed half my cock. Mara clenched her teeth, took a deep breath, and pushed her ass farther back. I kept advancing until I was completely inside her.

—Fuck… yes… —she hissed—. Stay there for a second.

I stayed inside, feeling the tight heat of her ass around my cock. Then I began to move slowly. One hand went to her clitoris and the other to her tits. I rubbed her pussy from the front while penetrating her from behind, alternating slow thrusts with deeper ones. Her body gradually relaxed until she began asking for more speed with little backward pushes.

Then I really fucked her ass. With appetite. Holding her by the waist, moving in and out forcefully, listening as her moans grew dirtier. She slipped two fingers into her pussy while I drove into her from behind, and seeing her masturbate while I impaled her pushed me to the edge.

—Don’t stop… I’m going to come… —she said, almost voiceless.

I pinched her clitoris, then rubbed it in quick circles, and felt her ass contract around my cock. She came trembling, folding forward, with a long spasm that left her legs unable to support her. I had to hold her up so she wouldn’t collapse against the door.

I pulled my cock out slowly. It was shiny and hard as a rock. She looked at me hungrily and knelt in the dirt without being asked. She grabbed my balls, licked me from underneath, and swallowed me whole again with an urgency that was no longer tentative. She sucked for real, noisily, with saliva, with the obscene devotion of someone who enjoys taking cock.

I came in her mouth a short while later, pushing her head with both hands. She kept her rhythm until she drew out the last drop, swallowed, and then showed me her empty tongue with the faintest smile.

—Now we can go run your supposed errands —she said.

***

We took a quick swim in a nearby cove to wash off the sweat and cool our skin. We avoided getting our hair wet so we wouldn’t return smelling of salt. Then we got dressed, made a couple of pointless purchases to keep up appearances, and continued in the car as if nothing had happened. But nothing was calm. The tension was still there, building again.

She was the one who suggested the next madness. She said the idea of fucking in a public place turned her on, somewhere we would pass every day afterward and remember what we had done inside. I knew a friend with a motorhome parked near his house, so I asked him for the keys on the pretext of moving it for a couple of hours. He never imagined what I wanted it for.

When we climbed into the motorhome, Mara closed the door and turned toward me with a smile that no longer hid anything.

—Here, I want to lose count —she said.

She didn’t even give me time to answer. She knelt in front of me and pulled down my swim trunks. She began by kissing my pubic hair, my groin, and the insides of my thighs, making me wait while I watched her face between my legs. Then she licked my balls with her flat tongue and wrapped her hand around my cock, squeezing it just enough before she began to suck.

She did it better than I remembered from the night before. Deeper, wetter, more shameless. She moved up and down, looking at me while she swallowed it, letting saliva drip down the shaft and spreading it with her hand. I grabbed her hair and she responded by moaning with my cock in her mouth, aroused by the humiliation of kneeling there.

—I want you to use me —she murmured as she pulled it out for a second—. But lie down first.

I lay down on the motorhome’s small sofa bed and she positioned herself between my legs. She lifted my thighs and licked my ass without hesitation, with the same naturalness other people use to give a kiss. Her tongue circled my anus slowly until it made me tremble. Then she spat on me, inserted a finger, and began moving it inside while masturbating me with her other hand.

It was a new sensation for me, strange at first and immediately addictive. Mara noticed and smiled like a satisfied bitch. She added a second finger, massaged me inside, and then went back to sucking my cock without removing her fingers from my ass. The combination left me half-crazy. I moaned like an idiot, my body tense and my legs spread while she did exactly what she wanted with me.

—Do you like it? —she asked, pulling away only to speak.

—Yes. Fuck, yes.

—Then turn around.

I put her on all fours on the narrow mattress. I spread her ass with my thumbs and watched it clench, still shiny from earlier. I spat on her, spread the moisture with the tip of my cock, and entered slowly. The motorhome creaked as soon as I began to thrust.

The cramped space made everything more animalistic. I couldn’t build momentum from far away, so every thrust came from the hips, short, hard, repeated. I grabbed her tits from underneath, then her hair, then her nipples. She pressed her face into the mattress and no longer bothered to hide her moans, asking me to fuck her harder, not to treat her gently.

—Destroy that ass —she said, turning her head just enough for me to hear her clearly.

I did. I held her by the hips and began giving it to her without pause, feeling her open more with every thrust. I moved one hand to her pussy and discovered that she was soaked again. I pushed two fingers inside her while fucking her ass, moving in and out at the same rhythm with my hand in front and my cock behind.

Her body began to shake. She touched her own clitoris, desperate, and ended up coming with a long, broken moan, so loud that for a second I thought someone outside might hear her. I continued for a few seconds more, hardened by watching her lose control like that, until I felt my orgasm rising up my spine.

I pulled out in time and she spun around like a spring to swallow me. She jerked me off furiously while sucking the tip and let me shoot into her mouth again. She didn’t lift her tongue until she had sucked me clean.

We lay there for a while, breathing, sweaty, our legs still trembling. But we weren’t finished. Not by a long shot.

Later, when I had recovered my erection, she sat on top of me facing me, guiding my cock into her wet pussy. She lowered herself slowly, biting her lip, and began riding me. The sway of her tits, her hands pressed against my chest, the way she opened herself to swallow me better… it was all too much.

I held her ass, burying my fingers in the flesh as she rose and fell faster and faster. At times I let her drop all the way down, then lifted her sharply and drove into her again. Mara insulted me in a low voice, aroused, asking for more depth, more rhythm, more force.

—Touch my clitoris —she ordered—. I want to come on your cock.

I obeyed. I rubbed her exactly where she needed it while she kept bouncing on me. Within seconds, she went rigid, her mouth open, and came in squirts, squeezing me inside her. I followed soon after, pulling out in time to come over her belly and tits. She brought her fingers to her skin, collected my semen, and put it in her mouth while staring straight at me.

That gesture, more than any of the fucking, was what finally blew my mind.

***

By the time we finally got dressed and aired out the motorhome, it was already midafternoon. My body ached from sheer exhaustion, and even so, I still got hard every time I watched her readjust her dress. On the drive back, Mara stroked me over my swim trunks with indecent calm, as if everything that had happened fit perfectly into a carefully controlled plan.

We talked about it with a coldness that didn’t match what we had just done. We said it had been madness, that precisely because of that it couldn’t happen again, that it was a miracle enough that we had come out of such a mess clean. We both knew that if we continued, we would end up destroying more than one life.

—We’d better leave it here —she said, without stopping her stroking—. Right now, while we can still look each other in the face.

I nodded. Not because I wanted to, but because I understood the disaster that would follow a second time. I dropped her off at her brother-in-law’s house. She got out of the car, gave me a calm smile, and walked away as if that morning she had gone with me only to buy some silly things in the next town.

We never fucked again.

But it wasn’t necessary. To this day, whenever I see a secluded cove, a badly parked motorhome, or a tanned woman biting her lip while holding a drink, I feel her nipples between my fingers again, her ass tightening around my cock, and that low, dirty voice ordering me not to waste time talking.

It happened only once. And precisely because of that, it has never faded from my memory.