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"You're awfully hard," Mariana whispered as she stroked Matt's cock.
He turned towards her and smiled. "I'm thinking about our trip to the coast."
It wasn't just their trip, of course. Diego would be joining them. In fact, Diego's presence was the entire reason for the trip. Nearly a month had passed since he'd come to town and spent the weekend fucking Mariana and she'd become increasingly desperate to feel him inside her once more.
Mariana released her husband's cock and took off her sweater, exposing her bare breasts and moving a little closer to him on the couch so he could feel her soft, perky flesh against his arm. Her fingers found his dick once more and she asked, "We're going to have all sorts of naughty fun on our trip...well, Diego and I are going to have fun. I suppose you'll do quite a lot of watching, won't you Matt?"
"Yes," he admitted.
"But you liked watching in the hotel room, didn't you?" Mariana asked softly before kissing his neck. She moaned to remind her husband of how it had sounded when Diego fucked her and saw Matt close his eyes. Mariana hoped he was picturing one of the times Diego had fucked her that weekend. Perhaps she was on her hands and knees in the bed. Perhaps she was riding his cock on the couch. Perhaps she was in the shower giving Diego a blowjob.
"Yes, I liked watching," Matt admitted.
"Tell me, Matt, would you like to watch Diego cum inside me?" Mariana asked.
He turned to her with a mixture of hope and lust in his eyes. "Did he...is he clean? Is he really going to cum inside you?"
Matt's excitement was obvious from the look in his eyes, but it was the way his cock swelled up in her hand that gave Mariana absolute proof that her husband loved the idea of another man cumming inside her. She was fairly certain she loved the idea even more than Matt - she'd been fantasizing about that very thing since she'd mentioned it to Diego - but Mariana loved that Matt was turned on, for that meant her fantasy was guaranteed to come true.
"Yes," she said. "He wrote me today. His said his test came back clean. He sent me a copy, in fact. We're going to fuck without condoms on our little trip. He's going to fuck your wife bare, Matt. He's going to cum in your wife's pussy over, and over, and over."
She leaned in, kissed and gently sucked on her husband's neck, and added, "And I can't wait, Matt. My pussy has been wet for three weeks just thinking about it. I get turned on every time I imagine him unleashing inside me. My body tingles with desire when I think about giving Diego that pleasure, about his cum filling my pussy and slowly dripping out of me long after I've satisfied him and he's made me cum the way only he knows how to do."
Mariana squeezed the head of Matt's cock and a shiny drop of precum appeared. She gathered it on the tip of her finger, held it up, and slowly placed that finger in her husband's mouth. Matt closed his lips around it, sucked gently, and moaned. Mariana wasn't sure what about it turned him on, but she loved that he was horny enough to be thrilled by something a little bit kinky.
"Are you excited at the idea of watching Diego cum inside me, Matt?" she asked.
"Yes," he admitted. "I don't know why, Mariana, but I am."
She took his cock in her hand once more and said, "Mmm, it doesn't matter why. I just love that you're turned on. I love that your dick is so hard. I love that you're dripping precum. I'll bet you'd like to fuck me, wouldn't you Matt?"
"Yes, fuck, Mariana, yes, I want to fuck you," he said.
Mariana smiled. "No pussy for you," she replied. His cock surged in her hand again, proving his excitement at being denied. "No pussy for you until Diego's had me. I'm saving myself for him. I want to be desperate for any kind of cock by the time I see him. I want to be dripping with desire when we drive up to that beautiful beach house he rented. I want to be unable to resist getting on my knees for him the moment I see him, Matt, which means no pussy for you."
Another big droplet of precum appeared at the tip of his cock. Mariana scooped it up, but this time she took the sweet treat into her mouth and swallowed it.
"You won't get any pussy over the weekend, either," she said. "Unless you want to eat my pussy after Diego's cum inside me."
Matt groaned and cum spurted from the tip of his cock. He looked surprised at first - Mariana was surprised at his sudden climax, too - but the pleasure quickly overwhelmed everything. She grasped his dick tightly and stroked him, offering whatever extra stimulation she could as his legs trembled and he leaned back, closed his eyes, and let the joy of an orgasm wash over him.
As she watched him cum, Mariana couldn't help but wonder if her comment about eating her messy, cum-filled pussy had put him over the top. It certainly seemed like that was the case, as he'd spilled his seed mere moments after she'd planted the idea of eating her out after Diego had enjoyed her.
She hadn't said it with the intention of arousing him. She hadn't really considered the idea of Matt going down on her after Diego had cum inside her, and yet it seemed that he found it thrilling, and Mariana didn't want to deny her husband something he found thrilling, especially if it meant there was a chance she'd get to have even more fun with Diego.
"Was that good?" Mariana asked after Matt had come down from his climax. She was curious about the source of his intense pleasure, but she wasn't going to ask for fear that he might be embarrassed about his desire.
Matt nodded. "It was better than good." A smile slowly crossed his face as he closed his eyes once more and inhaled deeply. "It was great. Can I make you cum?"
"You can go down on me," she said.
Matt grabbed his underwear from the floor, wiped up the cummy mess that had spilled on his stomach and thighs, and then got on the floor between Mariana's legs and went to work on her pussy. She put a hand on the back of his head, closed her eyes, and let thoughts of sex with Diego fill her head.
It didn't take long for a blissful orgasm to wash over her body as she imagined her pen pal and lover cumming inside her.

Later that night, Mariana sat in bed with her laptop open as she prepared to send Diego a message. Despite an orgasm provided by her husband's tongue, she'd spent most of the evening thinking about the man she longed to fuck again, the man who'd made her cum so many times over just one weekend and the man who she couldn't get off her mind as the weekend approached.
My Dearest Diego,
With only five days until we see each other again, I find myself struggling to think of anything other than the pleasure of having you inside me again.
I think of how you made me feel when you visited. I think of how hard you made me cum. I think of how many times you took me, filled me, fucked me, satisfied me...and I get wet just thinking about it. I get so turned on I can't think straight. Over the past few days I've been wet almost constantly.
It's not just the sex. It's not just your cock. It's not just your strong, sexy body I crave. It's the fact that you're going to cum inside me. I don't know why, exactly, but ever since you wrote to tell me that your test came back clean, I've been even hornier than usual. You've been on my mind every waking moment, Diego.
The more I think about it, the more I'm convinced that my body has come to crave experiencing that ultimate primal pleasure with you. I want you unfettered. I want no barriers between us. I want to feel your cock swell up the moment before you pump your seed into my pussy. I want you to claim me in the way a man claims a woman...and I want you to do it while my husband watches.
I know that might make me sound like a terrible wife and I'm not sure I'd ever admit that particular detail to Matt, but I just can't get that thought out of my head. There's just something so irresistible about it, something so naughty, something so hot. He's the one that should be cumming inside me, and yet my body wants you, Diego. It wants your cock and your cum. It wants you to claim my pussy, to take it, to fill it with your cum as many times as you can during our weekend together.
Of course, I might be sad if I don't get to swallow your cum at least once, so we'll have to make time for that, too. I plan on exhausting you this weekend, Diego, so I hope you're ready for that.
I can't wait to see you, to touch you, to kiss you, to suck your cock, to give you my pussy, to cum on your cock, to make you cum inside me.
I'll see you soon, Diego.
Mariana
She was drenched by the time she sent the message and closed her laptop, so Mariana retrieved her dildo from the nightstand, stripped off her panties, closed her eyes, and fucked herself silly while rubbing her clit and fantasizing about Diego's cock pumping thick ropes of cum inside her.
"Can I help?"
Mariana's eyes shot open and she saw Matt’s still damp, naked body standing at the foot of the bed. His cock was half hard cock and he had a smile on his face. Mariana didn't stop fucking herself with the toy, though, not for a second.
"Masturbate for me," she said. "Think about Diego fucking me while you do it. Think about his bare cock in my pussy. Think about how badly I want him to cum inside me, Matt. Think about him filling my pussy with his thick, hot, creamy load."
Matt dutifully wrapped his fingers around his cock and stroked as Mariana filled her soaked pussy with the big dildo. It moved in and out of her body with remarkable speed, at times pumping her faster than even Diego could manage.
"He's going to cum inside me, Matt," Mariana said as she arched her back a little. "He's going to cum in your wife's pussy. Is that what you want? Do you want another man to cum inside me?"
"Yes, please," Matt replied. "Yes, I want him to cum inside you, Mariana. I want him to cum inside you!"
She looked at her husband and smiled. His dick was hard as a rock and his balls looked tight, like he was on the verge of yet another orgasm.
"I want you to crawl between my legs after he cums, Matt," she said as pleasure surged between her legs. "I want you to crawl between my legs and lick my messy pussy after Diego's had his way with me. I want you to lick his cum out of my cunt after he's fucked me!"
Mariana spread her legs wider and her toes curled as an orgasm washed over her. She buried the toy as deep in her pussy as it would go and gently rubbed her clit, luring every last bit of pleasure out of her body in the process and enjoying yet another mind bending climax.
Matt hadn't yet finished, so Mariana pulled the toy from her pussy, set it on the bed, and beckoned him between her legs. He crawled forward, positioned himself so he could still masturbate, and stared at her pussy mere moments after the long, thick toy had stretched it out.
"What do you want to do, Matt?" she asked.
His hand moved up and down his slick shaft as he stared at her pussy and then slowly met her gaze. "I want...I want to eat your...your messy pussy, Mariana."
A look of intense pleasure washed over his face, as if uttering those words were enough to deepen his arousal.
"Then do it," she said. "Put your tongue inside me. Clean your wife's messy pussy after another man came inside her. Clean me and stroke your dick. Stroke the dick that isn't big enough to satisfy me, Matt."
Matt didn't last long. He didn't need to, though. Mariana just wanted to make him cum, and to stoke the flames of what seemed to be his fantasy.
"Was that good?" she asked after he'd cum.
"It was great," he replied.
She detected no shame on his face. She wasn't sure if he'd actually want to clean her pussy on their weekend at the beach, but she was definitely going to give him the chance, as it seemed like he was eager to walk a little further down the kinky road they'd already explored and Mariana had no trouble going there with him.