An Open Family Ch. 01 - Sisterly Lust

Summary: Brenda and her husband Harry, begin an open marriage that veers into the incestuous when Brenda's younger sister Becky comes to town and awakens something in her.

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"An open marriage?" Brenda asked, repeating the words her husband had just said.

"Yes. Though I guess they call it 'polyamory' now? I don't know, it's just this stuff I've been reading online." Harry said, showing her his iPad screen with some web article on it. Brenda took the iPad into her hands and read the headline aloud.

"What the hell is this? 'Could an open relationship spice up your marriage?', what the hell kind of websites have you been looking at?" She gave her husband a stern look, though internally, the thought of it made her... aroused. But still, she was hesitant.

Harry looked nervous. "Look, it's like I said the other night, it's not that I don't love you or anything and when you admitted the same to me I didn't feel 'betrayed' or whatever. We do sometimes think about having sex with other people. And we've had some fun with that. The roleplaying was great, so was the porn but..."

Brenda found herself nodding along, also thinking of the time she was blindfolded. Still, she felt she should feel offended. "But you're sick of having sex with me?" Brenda asked, eyebrow raised.

"No. No. I mean... well, aren't you sick of having sex with me?"

Brenda laughed and them sighed. She looked down at the floor for a moment. "I guess?" she said, eyes returning to her husband. "Kind of? But... not like... not all the time... just... look I know when we were younger, before we even met, I know you were a lot like me, having all kinds of 'adventures', but honey, we're in our forties now. We have two kids... I mean swinging? Really?"

"One of them's in college, the the other has almost finished high school. They're both doing their own thing now, we can let them off the leash a little, start focusing on ourselves a little more." Harry reasoned, placing his hands tenderly on her shoulders. "And yeah we're a little older, but you're still sexy as hell." He added with a smirk.

Brenda was struggling to look pissed. "And you're not too bad yourself." She said, stroking his face gently. "I'm not sure if I want to share you... you really want to share me?"

"I dunno, I don't really see it that way." He said thoughtfully, moving his hands down to his wife's waist. "We still kinda 'belong' to each other, it's just our relationship is bigger than just sex, right?"

She nodded slowly. "Honestly... I want this. I think we should try it at the very least, see how it goes... but..." She sighed, "It's not that I don't trust you but I think we need some rules."

"Rules?"

They spent the rest of the afternoon agreeing on rules, doing the best to respect each others boundaries. Among many other things, they both agreed to keep things quiet, they didn't need everyone to know about their 'arrangement', especially their kids. They both agreed to keep each other informed of who they were seeing. They agreed not to bring dates home. They agreed to use protection. They agreed not to sleep with anyone the couple were too familiar with. And they agreed that every Sunday evening they'd have sex with each other and only each other.

That evening, the two of them felt far more emotionally connected, far more understanding of each others' needs and desires. Before going to sleep they had some of the most impassioned sex of their long relationship.

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It had been well over a year since Brenda and Harry had that conversation. Since then, some of those rules had gone out of the window, though of course, not before they discussed things first. This usually happened after their Sunday love making session. They would hold each other in the dark and talk about a few of the 'adventures' they'd had that week and some of the 'adventures' they wanted to go on. What became clear was that both of them wanted to sleep with people both of them knew and were quite familiar with. Though both had expected to feel more jealous when this open relationship began, the couple found they were far more evolved than they realized.

It had started when Brenda ended up sleeping with Mike from her work. Harry didn't mind this breach of the rules, nor did he mind that the two of them would sleep together quite often. In fact he enjoyed Brenda telling him all about her sessions with Mike. Likewise, Brenda got off on Harry telling her all about how he'd end up sleeping with their son's attractive young English teacher Miss Sharp. This led to the two of them sleeping with people far more familiar. Harry would occasionally visit Stacy, a single mother living a couple doors down. Brenda would regularly have 'brunch' with Edith, her close friend living across the street. Both had been on dates with old flames. The two had also ended up 'partner swapping' with Mindy and Todd, a couple they'd been friends with for years.

Brenda loved it, this growing network of friends and acquaintances that were secretly sexually involved with the couple. She sort of understood the appeal of sex with a stranger, and that was often fun - going to a bar in a very short dress and leaving with any random guy who didn't give off a serial killer vibe. But still, there was something about taking a pre-existing relationship and adding a sexual element that really got her going. Harry seemed to feel the exact same way and Brenda loved the fact that they were so likeminded.

Things got a little crazy when both Brenda and Harry mentioned the cousins they'd had little flings with back when they were in their teens. Though at first hesitant to bring family into this, they'd ended up succumbing and ended inviting a few of them over for a little more than dinner. For instance, Brenda invited over her cousin Charlie over for an evening. And after a pleasant dinner followed by some wine and light conversation by the adults, Harry left the room at Brenda's signal, leaving Brenda to remind her still very attractive cousin, about their first time together.

That was another rule that had changed, bringing 'dates' back to the house. It ended up just being more convenient when a date's home was unavailable and the cost of motels started stacking up. Harry and Brenda ensured they were respectful of each other and one would happily use the guest bedroom when the other was in the master bedroom. Their son Sam, it appeared, was none the wiser to any of this, constantly out of the house or up in his room with his gaming headset on full volume.

They were glad about this, eager to continue with this lifestyle but worried their kids might get upset if they found out. With their daughter Jenny off at college, there was less chance of her noticing and they took care to limit their dates on the weekends when she was back, though they preferred spending the evening catching-up with her anyway.

Still, however, they were worried it was getting risky, especially with them taking it to another level by sharing other people as a couple. One or two of Brenda's friends, one of Harry's. A couple of times with Sam and Jenny's old babysitter Maddie. Quite often, especially when Sam was out, Brenda would invite over her old college roommate Patricia. They'd also shared one of Harry's cousins, Chris, the guy he'd first explored his bisexuality with. That had been a very fun evening for all three of them. Though more often than not, they'd been meeting strangers through swingers' dating sites online, but that made the more familiar partners all the more exciting.

They had also enjoyed watching each other with another partner. A number of times Harry had joined Brenda and Edith for 'brunch'. Edith wasn't too into the idea of Harry joining in but she found the idea of an audience very appealing. Brenda had also spent a couple of evenings with Harry's best friend Drew while Harry watched from a corner. Brenda also loved doing the same, watching her husband with some bimbo he'd met at some bar or else with this Julius who he'd met at the gym.

That was the other thing, both of them getting to explore their bisexuality again. Being with a woman was a whole different sexual experience to being with a guy and Brenda felt that both she and her husband needed both. Even with all the LGBTQ acceptance going on in the world, she'd never truly felt included in all of that, her and her husband previously living this very hetero lifestyle. But going out and spending more time with other gay and bi women, especially the younger ones she'd meet at clubs Edith would take her too, she felt more herself than ever before.

All of this had been great for the couple. They felt genuinely happier. Sometimes they felt a little 'sexed out' and would take a little break, except from each other of course. That sex also seemed to improve. They'd both learned a few new things which enhanced it but more than that there was this stronger emotional bond between them. Sex with Harry felt more special to Brenda. It felt more comfortable, more relaxed. Sometimes the guys could be a little rough and the girls a bit demanding. Sex with other people often felt a lot more performative. With Harry she felt like she could be herself a lot more. And there seemed to be lower expectations too. They could be as quick as they needed to be, both knowing exactly the best ways to get the other off. With Harry, it wasn't sex for the sake of sex, it was a chance for her to be intimate with the man she loved more dearly than anyone else in the world. But this didn't mean she regretted opening up her relationship at all. All that sex with other people was a lot of fun. And sometimes you want to go out and have an adventure, but more often you just want to sit at home and watch TV. But all the same, it made her appreciate Harry all the more.

Still, at points, it felt like they had gone a little too far with this, like with what happened with Brenda's sister.

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Becky was Brenda's youngest sister, still in her late twenties. They'd never been super close growing up but they'd grown closer as adults, when Becky had attended grad school in the city Brenda and Harry lived in. Brenda was surprised how similar Becky seemed to be to her. A real party girl, they'd stay up late in the evening talking about all these guys she'd be 'hanging out' with, reminding Brenda a lot of her own college experiences. Though what amazed Brenda was how well Becky seemed to balance her night-life and social-life with her intensive studies in bio-chemistry. Brenda had just scraped by, her spending most evenings out and most mornings hungover. And not only was Becky smart, she was gorgeous. A perfect body, a very pretty face. She tended wear tight clothes that really hugged her figure. Sometimes Brenda would catch Sam staring at Aunt Becky and a few times she'd noticed her husband doing the same.

Several years later, long after Becky had moved upstate to work at a large food testing lab, she would still occasionally visit her older sister and her family, staying with them for a few days and catching up with Brenda. It was on one of these occasions, after the open relationship had begun, that Brenda had suggested Harry maybe spend some time with Becky. After dinner, Sam had gone upstairs and the three adults had spent the rest of the evening with a bottle of wine or two. When Becky had gone to use the bathroom, Brenda had made the suggestion to her husband, noticing how flirty Becky was being with him. Harry was a little reluctant but Brenda was encouraging, knowing her husband really had a thing for her. Brenda left them alone for maybe half-an-hour and before she knew it, the two of them had disappeared into the guest bedroom for another three hours. Brenda pressed her ear against the bedroom door and heard her husband making her sister moan. She bit her lip and stroked herself as she listened.

She awoke the next morning, a little hungover from the wine, her husband laying next to her. Remembering what had happened the night before she had mixed feelings now she was sober, still she asked Harry if he enjoyed himself, her husband couldn't wipe the smile off his face. Still though she felt weird about about it like this was way too depraved, even for them. Becky was single so it's not like there was some other guy being hurt by all this, but she was still her little sister. But it's not like Brenda actually felt bad about it, it's more that she was worried that she should feel bad but didn't.

Becky woke up at around noon, long after Sam had gone to school and Harry off to work. Brenda had taken the day off to spend it with her sister. Becky found Brenda in the kitchen. The younger sister seemed a little nervous, approaching Brenda cautiously. "Did you have fun with my husband last night?" Brenda asked, putting on a stern voice.

"Shit!" Becky exclaimed. "Look he said you had like an open marriage or something, I was drunk and stupid enough to believe him, I'm so sorry..."

Brenda burst out laughing and admitted she'd put Harry up to it. Becky complimented her husband's performance and asked a little about their open marriage situation. Brenda made her sister some breakfast and told her all there was to tell, Becky very amused by the tales. "Its good to know you two are still active in your old age." She teased.

"Hey now, I'm only 42!" Brenda laughed, jokingly waving her spatula at her sister in a threatening manner.

Becky held up her hands in faux-surrender. "Hey, just kidding," she grinned. "Hell, I'm into the whole older partner thing. So hard to find a good DILF."

"DILF?"

Becky giggled. "It stands for 'Dad I'd Like to Fuck', pretty much any older dude but, you know, him being an actual Dad doesn't hurt either." She smirked.

Brenda laughed and shook her head. "Honestly we'd have probably tried doing this sooner, but you know, the kids and everything. But they're more self-sufficient now, you know?"

"I think it's cute. You two finding ways to have fun but still sticking together. God I wish I could find a guy like that, I just get bored of them too easily. Not just the sex, even their faces, I get sick of seeing them. Longest relationship I had was like a month long and by the end we were just arguing all the time. Not even like fun, sexy arguing with make-up sex after." She sighed.

"You'll find that person eventually. I was a little like you until I met Harry." Brenda said, consoling her sister a little.

They talked until Sam came home from school. Brenda smirked as she watched her son trying to 'subtly' check out his Aunt. When he left both women giggled. "He's cute too, looks a lot like his Dad. He got a girlfriend yet?"

"I think so, he doesn't tell me much." Brenda confessed. "I sometimes walk in on him texting people and he gets all hot and bothered, must be girls. Maybe guys, who knows. Maybe you should do some probing, he likes you." Brenda teased. "You can find out exactly what he's into."

Becky giggled and shook her head. "You husband is one thing, your son.... well he can look all he wants." She said with a wink. "Speaking of Harry, when does he get back?"

"In a couple hours... are you that eager for a screw already?" Brenda smirked.

"Maybe. You know that thing you were telling me, about watching Harry fuck all these girls, that does sound super hot, being watched I mean. I mean, I wouldn't be against it, if you wanted to?"

Brenda's face turned very warm. "Well I did enjoy the sounds I heard last night. I wouldn't mind seeing it as well."

Harry was similarly eager to do this, as well as eager to have some more fun with his sister-in-law. The three of them opened another bottle of wine when Sam had gone upstairs, though they only made it halfway through before they decided to head to the bedroom. Brenda sat back in the big, pillowy armchair she and Harry usually watched each other in. She swirled the wine around in her glass and watched her husband and sister stripping clothes off each other as they made out.

Harry was tall and broad, Becky a lot shorter and more petite so it made for an interesting sight. Harry lifted her up in his large arms and Becky wrapped her legs around his body, their lips still locked. Brenda watched this, her pants and panties on the floor, touching herself gently as she watched the two fall onto the bed in a lustful embrace. She watched Harry put his glasses aside and push his face deep between Becky's thighs. Her sister cried out and giggled. "Didn't even have to ask. Is your hubby the best or what?" She grinned, giving Brenda a wink.

She lay back, her long dark hair fanning out behind her head as she caressed one of her large but perky breasts. Harry gripped each of her thighs in his big hands and pushed his tongue in deeper and deeper, before moving his lips up and wrapping them around her clit. Becky put her fist in her mouth to avoid screaming, conscious that Sam's bedroom was just across the hall.

As Harry and Becky proceeded, Brenda couldn't help but have those weird feelings again. Watching her sister being pounded by her husband, why didn't that upset her, why did that arouse her? It wasn't just the act itself, it was Becky's gorgeous body, the sweat beginning to glisten off of it as Harry mounted her. It was the shape of her ass, the curve of her breasts, her face as she smiled with pleasure, the sounds of her moans. Brenda wished it was her fucking Becky right now, Harry sitting and watching. And that would have been a perfectly normal feeling, she thought, if Becky wasn't her sister. Cousins were one thing, a sister was an entirely other thing... wasn't it? Something inside her ached, wishing Becky were bi, or even just a little bicurious, so that she could join in the fun. So that Brenda run her own hands over her sister's body, kiss her lips passionately, make her sister make those sounds by her own hand.

She had floated the idea to Becky before, over the wine, Becky had politely refused. "I mean you're my sister, watching is one thing, I dunno about like... touching and stuff. Besides, I'm just not into girls. I did make out with my roommate once and nothing, and another time I did have a threesome with my friend and her boyfriend, but god that was boring. Girls just don't do anything for me Brenda, sorry."

Though a little disappointed, Brenda laughed it off, "It's fine, I forgive you being straight." She giggled. "As long as you and Harry have a good time, so will I."

And that was the truth of it. The whole thing was still incredibly arousing, but it was much like porn, wanting to touch the people performing in those scenes yourself but the screen acting as a barrier. Of course there was no barrier here, but she wanted to respect Becky's boundaries.

"Anal?" Harry asked Becky casually.

"Oh fuck yes." She laughed. "Best brother-in-law ever." She gave Harry a long kiss before laying on her front. Harry gripped the cheeks of Becky's perfectly round ass. He pleasured her with his fingers and tongue before laying atop her once more and pushing his cock all the way in. Becky screamed into the mattress and gripped the sheets. Brenda was moaning herself, watching the scene intensely, pushing her middle finger deep inside herself while her thumb rubbed above. Something wet spilled out of her and into the armchair. The seat had become filthy from Harry and her using it for this.

The two on the bed kept going a little while longer until Harry finally emptied himself into Becky. He withdrew and collapsed on his back next to her. Becky too remained, laying flat on on her face, with just enough energy to wrap an arm around Harry and give him a quick kiss.

Brenda broke into polite applause, finally moving over to the bed to give them both a loving kiss on the forehead. Her sister's sweaty naked form lay there so tempting to touch, but Brenda kept herself under control. Becky rolled over to face Brenda. "Thanks for letting me fuck Harry." She smiled. Her face was content and peaceful. "He really knows how to treat a lady." Harry remained silent next to her, smirking at the comment, still breathing a little heavily.