Sarah held her sister tightly, preventing her from disappearing beneath the waves. Linda sputtered, taking several deep breaths as the young woman helped her to her feet.

“Are you guys all right?” Billy shouted in the distance. 

Sarah kept her hands around Linda's waist until she was sure her sister could stand alone.

“Sis, you gotta watch those waves,” Sarah furrowed her brow, examining Linda’s face. 

What the fuck?

Sarah felt strange being the one giving words of caution to her older sister. Linda gazed back, mouth agape, a strange expression on her face. She smiled.

Goddamn, that felt good.

“Sis?” Sarah raised an eyebrow. She remembered how her sister’s body was jerking as she pulled her up from the sea floor. It was not something unfamiliar to the seventeen-year-old.

“Yes, I’m okay,” Linda managed to stammer out. “Don’t worry, I wasn’t in any danger.” She had to shout above the next approaching surge. “I just love these waves so much I got lost for a moment.”

By now, Sarah was looking at her sister with a simultaneously puzzled and comical look on her face. Always the perceptive young woman, she realized what her sister had done.

I bet you love these waves, Sis. Why don’t you just masturbate in private like the rest of us horny girls?

“Okayyy, then.” Sarah raised both eyebrows, still processing what had happened as she wrapped her arm around Linda’s waist. The next wave pushed them toward the shore.

God, my big sister needs sex about as much as I do!

Billy waded up to the two women as they trudged out of the water, placing a hand on his mother's hip as they walked her back to dry land. Linda felt wet fabric clinging to her body and sand between her toes as the sea's rumble fell behind.  No doubt her erect nipples were poking against the thin barrier of her practically non-existent bra and cotton blouse for all to see. She looked around the beach, the stupidly innocent grin returning to her face. The next moment, Mother returned.

“Let’s build a fire and dry off,” Linda said, slapping her son on the ass with a wet smack. “I think we have some wood left over from last year.”

“Sounds good to me!” Billy broke into a run toward the house. He was no stranger to the weather-worn bin where they kept any usable pieces of driftwood or burnable items they came across.

“And watch out for spiders and god knows what else!” Linda added, shouting after her son. “I don’t want you in the emergency room!”

“Okay, Mom, okay!” The young man’s voice faded as he circled around the back of the house. 

“I know, I know,” Linda said, mostly to herself. “He’s all grown up.” A heavy sigh and another squeeze around her kid sister’s waist. “Dammit, both of you are all grown up.”

Sarah didn’t respond, but merely nuzzled her sister’s wet shoulder, her eyes resting on the two thick, erect buds straining against Linda’s blouse. Although she could have easily let go of her waist, they were far from the waves by now, she enjoyed the contact and squeezed her tighter. Still, she couldn’t avert her eyes from Linda’s proud, albeit matronly, tits.

God, those nips are like rocks when they get hard. I wonder what they’d feel like in my mouth?  Mmmm…

Sarah felt heat rising in her body. The thought of suckling Linda lingered in her mind involuntarily, and this wasn’t the first time.

Damn, Sarah-girl, are you a fucking perv or what? That’s your sister, the one who raised you! Still…

Visions of her mouth on Linda’s tits persisted, much to her chagrin. It wasn’t like Sarah had never seen her sister naked. They were siblings, dammit! As Linda grew older, she was less and less inclined to expose her body to anyone, feeling a sense of shame with her aging body. Sarah couldn’t shake the feeling of her pussy starting to throb, getting all wet, her clit growing erect.

Come to think of it, I need to get off, too.

By the time they got the fire going, the sun was practically gone. They pulled out some ratty old blankets from the hall closet and spread them across the sand. The steady rhythm of the waves was joined by crackling licks of flame, wavering light playing upon their bodies.

Linda uncorked a bottle of unexceptional, but palatable, cabernet. She filled three Dixie cups half-full and passed them around.

“I guess you kids are old enough for a little of this.”

“Oh, my!” Sarah’s voice conveyed slight mockery. “I’m not sure I can handle it!”

Billy slurped away, crinkling his nose at the dry, slightly bitter liquid, unimpressed.

“Oh, I’m sure you’re no stranger.” Linda playfully smacked her sister on the thigh. 

“I’m not telling,” Sarah replied, smirking, trying not to down in one gulp the ridiculously modest portion swirling in her cup.

In time, talk waned into silence as everyone stared at the fire, waves crashing in the background, a ritual that had been repeated by the beach’s inhabitants down through the ages even before Linda’s distant ancestors ever thought about this place of retreat and solace. All three of them ended up in a bundle, their bodies pressed together, sharing warmth and love, sleepily staring at the last feeble licks of flame, then glowing embers. This level of closeness among the three could only happen at the beach house. Linda, mildly drunk and totally relaxed, reluctantly spoke.

“I’m going inside, kids,” she murmured, kissing each one of them on the cheek.  “You can stay out here for a while longer if you want.”

Neither Sarah nor Billy wanted their soft, warm heat source to leave. Their sighs almost sounded like groans of protest.

“But you can’t sleep out here. Who knows what weirdos walk the beach at night or, even worse, some drunken college boys on the prowl.”

"Oh, gods forbid," Sarah whispered, lips caressing Linda's shoulder. The wine had affected her, too, much to her surprise. Big sister had replenished her cup a few times during the evening. For a moment, she luxuriated in the softness of Linda's shoulder, inhaling the gentle musk of her skin. "I'll be passed around and ravished."

“Oh, Jesus, Sarah.” Linda placed another kiss, this time on her sister’s forehead. “I don’t think I'm overreacting, even though you ARE an adult now!” More goading sarcasm.

Sarah pulled away with a snort, rolling over on her side, and stretching out on the blanket like a slender cat.

Linda looked down at her son to rouse him, paused, then shook her head.

This is where my boy ends up?

She smiled. Billy’s face was sleepily buried between his mother’s breasts. He was oblivious to what he was doing, or so it appeared. Getting out of the house, far away from the city to the seashore changed all of their personalities to an extent.  Mother didn’t push her son away. The pressure of his face between her breasts, even though shielded by gossamer layers of bra and blouse, brought back fond memories.

God, it’s like when he was a baby, nuzzling my tits to no end. Damn, I can’t say that it’s unpleasant, like when I used to nurse him. Shit, now I have to get him off me.

"Honey, wake up." Linda hated to pull him away, but exhaustion and the gentle haze of alcohol were overtaking her and she needed a good night's sleep. Billy let out a whimpering groan and flopped back on the blanket, arms spread out. What Linda saw next made her stifle a gasp.

Oh, my god!

Linda’s eyes couldn’t help but be riveted on the vision before her. Billy had sprouted a full erection! The sight of his cock straining against the fabric of his shorts forced her to focus. She knew she shouldn’t be gazing at it, mouth open, but Linda couldn’t avert her eyes.

Jesus Christ! My boy's grown a lot and in every way!

A loud snort snapped her to attention. Sarah’s face appeared to her sister’s left, also gaping with surprise and amazement, unable to stop looking at her nephew’s impressive tentpole.

“Shhh…”  Linda admonished her sister quietly, putting a finger to her lips.

“Oh. My. God!” Sarah mouthed with a grin, eyebrows raised, shifting her eyes between Billy’s cock and her sister’s face.

Linda patted Sarah on the shoulder, her chin arcing toward the house. She spoke loudly in an attempt to rouse Billy from his comatose state.

"On second thought, let's all go in." The two siblings gazed at each other as they shared a mutual realization. Billy was now all grown up and packing! It was an even mix of amusement, embarrassment, and awe at the fact he seemed totally unaware of the display he was putting on.

“Come on, Billy, get up!” Linda reached out to tousle his hair and noticed her hand was shaking. She didn’t want to poke him in the stomach and take a chance on accidentally bumping into his throbbing boner.

Jesus, help me, I can’t stop looking at that thing. Linda, that’s your son. Stop it!

She hadn't wrapped her hand around a solid shaft of man meat in years, and couldn't help but imagine how something that proud would feel in her hands, her mouth, and her needy pussy. Blood rose in her cheeks as she fought away shame.

I could use a lover built like that, but not my boy, so why am I thinking this way?  Not having Dolores around is really making me crazy! And Sarah’s right behind me, watching. What’s going through her mind right now?

She regained a modicum of control and returned to the moment. “I’m about to pass out and don’t want you spending the night out here.”

Sarah had already stood up with her blanket in tow.

“Awww, Mom.” Billy finally sat up, still oblivious to his erection.

Linda took the other blanket as her son came to life, running toward the house, his cock pointing the way. With only the waning gibbous moon illuminating the blackness, the two women lagged behind, exchanging glances. Sarah smirked again, shaking her head in disbelief. Linda shouted after her son.

“But we all need to shower off. Those bedsheets are clean and I want to keep them that way!”

Billy, the little fucker, always made sure he was first to shower, and he wasn’t quick to finish. By the time he was done, the two women had to make do with lukewarm dregs from the feeble water heater. His mother chastised him for this every summer, but always, he seemed to forget.

“Son, get your ass out of there!” Linda poked her head into the steamy bathroom.  “I’m not taking a cold shower yet again!” The warm effect of the wine was tapering off.

“Okay, okay!” Billy reached out from behind the shower curtain to grab a towel.  “Don’t have a cow!”

But years of this behavior had made it a touchy subject with Linda. “Goddammit, I tell you not to hog the hot water again and again. What am I going to do with you?”

Billy gave his mother a flash of bare buttock as he fled, the too-small towel wrapped around his freshly-showered body. Linda felt like ripping the towel away and giving him a good hard smack.

Sometimes I want to smack him senseless! Cute butt, though.

Glimpsing her son’s unintended nakedness lessened her anger somewhat. She was still fighting images of his healthy cock, straining to be free. With an exasperated sigh, she turned the water back on, testing the temperature of the anemic spray. Sarah lurked in the doorway for a moment, then walked up next to her sister.

“Well?” she asked.

“That turd,” Linda said, scowling. “Want to share?”

“No problem,” Sarah shrugged, as she peeled her clothes off along with her sister, discarding them in the corner. Although the two women didn’t make a habit of being naked around each other in the city, here at the beach house, it was a regular occurrence, especially with Billy’s showering habits. 

Linda pushed the shower curtain aside and stepped into the tub, Sarah following closely behind. 

"You go first," Linda instructed her sister, who stepped into the room-temperature spray of the shower, quickly rubbing soap on her face, underarms, and lower regions. Aware of the limited hot water, she passed the bar of soap to Linda, who did the same.

“What do you think? About eight inches? Nine?” Sarah mused.

“What?” Linda didn’t understand. “What are you talking about?”

“Oh, come on.”

Linda paused a few beats, then she snorted. She had placed the soap back in its dish and, with her kid sister, was quickly rinsing off, racing against the ever-cooling water.

“Oh, Jesus, Sarah!” She gave her naked sister a dumbfounded look. Big Sis couldn’t help but admire how much her body had developed in the past year or so. She had become a woman.

“Well, I know we’re thinking the same thing,” Sarah replied. “Even if he’s your own son!”

Linda balked, refusing to admit the truth. “I am NOT thinking about my son’s genitalia, much less its size,” she lied. “You’re sadly mistaken.” By then, her voice didn’t sound very convincing. The now-cold water only added to her agitation as she slapped vigorously against her flesh to remove the slick, soapy residue.

Bemused at her sister's plight, Sarah was also appreciating some naked skin.  Linda, despite her low opinion of her body, still presented an appealing vision of mature womanhood. The young woman couldn't stop glancing at her sister's full, brown bush, now glistening with water droplets, or her motherly tits, capped by succulent areolas and erect nipples.

And to think I nursed on those so many years ago.

After a pause, Sarah replied, "Yes, you are.” She giggled and, with loving hands, helped her sister rinse the remainder of the soap from her back. Linda sighed, responding to Sarah’s touch.

“It’s not something you choose to think about,” Linda murmured as she conceded to her teasing sister. With that statement, she shut off the water, faucet handles screeching. “Okay, Sis, enough talk about Billy’s…” Another pause. “…You know.”

Sarah didn't reply but stepped out of the tub with her sister. They shared a towel, rubbing each other's backs. Linda pulled a couple of cheap bathrobes out of the closet, tossing one to Sarah.

“Here,” Linda teased. “Cover yourself, you shameless exhibitionist!”

“Okay, okay.” Sarah slipped into the capacious garment, glad to be clean, luxuriating in the feel of fabric sliding across her bare skin. “God forbid any naked women be roaming around this house.”

Linda noticed her own robe had become a bit smaller since the previous year, much to her chagrin.

There’s no way I could have put on weight since last year. Never!

Still, she pulled the robe snugly shut as her breasts protested their new confines.

If I didn’t have two hormone-laden teenagers around, you’re damn right I’d go naked.

Linda grabbed a soft, white pillowcase from the closet before switching out the bathroom light.           

By the time the two women exited the bathroom, Billy was ensconced in his room to the immediate left, transistor radio pressed to his ear. Linda knocked twice and opened his door. She could hear the tinny warbling of the disc jockey’s voice, hyping some new hit single.

“Good night, son.” Linda regretted barking at him previously, although he thoroughly deserved it. “I’m sorry I yelled at you.”

It took Billy a moment to respond, he was so caught up in what the DJ was saying.  “It’s okay,” he replied, distracted. “G’night, Mom.”

“But next time, Sarah and I will shower first!”

No response. 

Linda pulled the door shut and walked to her own room, bare feet creaking on the old steps as she descended to the ground floor. Sarah was already there, curled up atop the blankets, reading her trashy pulp romance novel. Linda took pause the moment she gazed upon her sister. Sarah had changed into a sleeveless nothing of a nightgown which dipped way below her neckline and stopped at the tops of her slender thighs, leaving nothing to the imagination.

What is with her? She might as well be naked. 

Linda could clearly see the outline of her nipples, surrounded by diminutive, pink areolas. Sarah's heels pressed firmly against her bottom, concealing any view of her nether regions. The thought of making Sarah change into something more concealing flitted across Linda's brain, but she was too tired to start any conflict at that late hour.

Ah, fuck it.

"Jesus, I'm beat," Linda said. Sarah, engrossed in her paperback, barely grunted.

Linda slipped the robe off her shoulders, hanging it on a hook, next to her sister’s.  Sarah looked up from her book.

“Hubba hubba!” She chuckled, making a wolf whistle as she made a show of scanning her sister’s nakedness.

“Oh, you hush, young lady!” Linda reached into the closet to retrieve her own nightgown. Fresh air wafting through the open window caressed her bare body, making her hair stand on end. Linda stifled a gasp.

Mercy, that breeze feels good. I can feel it on my nipples. Maybe I should just sleep nude. What would that little smartass say then?   

Of course, she thought better of it and slid the sensible, Montgomery Ward flower-print cotton nightgown over her head. Like her sister’s garment, it lacked sleeves, but the fabric was enough to conceal her body and the hem stopped just above her knees. She then slipped under the blankets, next to her sister. Linda couldn’t help but stare at the young woman’s near-naked body. From that angle, she could see Sarah’s downy pubic mound and a hint of labia.

Just as I thought.

“Aren’t you cold wearing just that?” Linda asked, eyes lingering on her sister’s pussy. “No panties?”

“I’m fine, thanks.” Sarah shot her a glance, eyebrow raised. “What are you looking at?”

Linda jumped slightly, her eyes suddenly looking up to meet her sister’s.

Caught! Think fast, Linda.

“Make sure you wear that robe when Billy’s around.”

Kid sister’s glare could’ve pierced armor in that instant.

“Jesus, Sis!” Sarah huffed. “Okay, I will!” She returned to the book, muttering under her breath. “Fuck, I just want to be comfortable. We are on vacation!”

"I'm sorry, honey." Linda wanted to touch Sarah lovingly but refrained. "But this evening has proven that my son, your nephew has grown into a young man.  He’s obviously no longer a...