20-year-old Percy Jackson was quite happy in his relationship with Annabeth Chase. Really happy, even. He'd never given a moment's thought to trying to hook up with any other girl. Why would he when he had such an amazing, not to mention sexy, girlfriend? They had a great relationship and an equally satisfying sex life. He needed no girl but her.

But then he saw Piper McLean in a two-piece bikini, and everything changed.

It wasn't as if Percy wasn't already aware that Piper was a beautiful woman. He did have eyes, after all. Of course he'd noticed her beauty, even if no one could compare to Annabeth in his eyes. Percy found it difficult to imagine any daughter of Aphrodite being ugly to begin with, but she wasn’t haughty about her beauty like some of Aphrodite’s children were. If anything, she seemed almost embarrassed about her attractiveness most of the time.

Maybe that was part of the reason seeing her in her bikini left such a mark on Percy. She wasn’t trying to be sexy or seductive. She was just lounging by the pool, relaxing and getting some sun, oblivious to Percy standing just behind the tree and staring at her. She was on her belly, so he got a magnificent view of her legs and butt. Her legs were nice, but Piper's ass was a thing of beauty, perfectly rounded and looking delicious, lightly slathered in sunscreen as it was. She'd wedged the bottom of the two-piece between her cheeks while out in the sun, so Percy got to see far more of it than he ever had before.

He could already tell that something inside him had changed while staring at Piper’s ass, but then she rolled over onto her back, and Percy got to see what the front side of her body looked like in her black two-piece. As one might expect, his eyes went straight to her chest. Her breasts were enticing enough as she lay on her back in the bikini, but Percy watched from just out of view as Piper sat up slightly in her chair, making them jiggle.

And then, after looking around and not seeing any of their friends around, she reached behind her back, undid her top, and let her breasts out. Percy stared hungrily at Piper's bare tits, knowing instantly that he couldn't do the proper thing anymore. The chance for him to walk away and try and forget what he'd seen had already been gone, but now he was going to have to act. He loved Annabeth, and he was content in their relationship. Piper also seemed happy with Jason.

Percy didn’t give a shit anymore. He had to have Piper. After seeing her in her bikini, it was all over. His relationship with Annabeth, great as it was, could not stand between him and the Cherokee beauty lounging by the pool. And her relationship with Jason was no concern either.

“Hey there, Piper,” Percy said, announcing his presence as he stepped out from behind the tree and walked towards her. It was time to seduce her away from her boyfriend.

--

Percy did not have much experience with seduction. Hell, who was he kidding? He had no experience in seduction. He didn’t have the first clue about girls or how their minds worked before he and Annabeth got together, and he felt like he didn’t know much more now.

That didn't really seem to matter because it hadn't taken much talking or seduction at all before Piper sat up in her lounge chair, pulled his swim trunks down, and started sucking his dick.

He would admit to being surprised at how easy it had actually been. Seriously, this was the girl with the ability to Charmspeak. If anything, she could have talked him in circles and convinced him to do whatever she wanted him to do. But she'd quickly gone along with his flirtations, and she hadn't even bothered to suggest that they sneak off somewhere more private to fool around. She just sat up in her chair, pulled his trunks down, and got to work. It was an incredibly bold thing to do, especially given how exposed they were out here by the pool. Jason and Leo were off doing their own thing in town, Frank and Hazel were enjoying some private time, and Annabeth said she was going to relax in her room for the afternoon, so it should just be the two of them by the pool for at least an hour or two. Still, what if someone came back early? There would have been no hiding what Piper was doing. She was sucking his cock, and she wasn't even trying to be quiet about it.

What was it that made Piper so eager to jump at his flirtation? Was she secretly not as happy with Jason as it appeared on the outside, or could their sex life be unfulfilling? Hell, maybe Piper was just horny. Percy didn't know, and he wouldn't take any time out to try and get to the bottom of it. He just stood and let her suck him, enjoying his good fortune.

If her sex life with Jason really was unsatisfying, Percy seriously doubted that it was Piper’s fault. She gave incredible head. Seriously, any girl who could deepthroat Percy's cock, as large as it was, had to be capable of blowing any man's mind with her mouth. Her lips twisted up and down the length of his cock, and similarly, her head twisted and bobbed as she took him all the way down. With apologies to Annabeth, Percy had never had his cock sucked quite like this. His girlfriend generally focused on his cockhead and used her hands to play with his balls for a bit. While that was effective, the messy, loud, sloppy sucking that Piper treated him to by the pool had him groaning and running his hands through her chocolate-brown hair within minutes.

Piper was an excellent cocksucker, and she knew it. Her eyes looked up at him often, following his interest and making sure she had his undivided attention. There was no need for her to worry about that because right now, by the pool, he was all hers. The team could have come back right now, and he wouldn't have given a fuck. Hazel could be scandalized by him getting his dick sucked out in the open. Jason could find his girlfriend blowing another guy behind his back, slurping all over his cock, and getting her chin and cheeks smeared with saliva as she gave it her all. Annabeth could come down and discover that hers were now not the only lips to stretch wide around Percy's cock. Damn the consequences; Percy didn't care what happened as long as Piper continued to cram his cock down her throat by the pool.

“Damn, you know how to suck a cock, Piper,” he praised, grabbing her hair. Her eyes danced with mirth and pride, and she slurped even louder on his dick. “You look perfect just like this. But I bet you’d look even better with my cum all over your face.”

The suggestion was thrown out impulsively, but after it came out, he was interested to see how she would take it. She didn't leave him guessing for long because she pulled her mouth off of his cock and started stroking him. Her hand was a blur as it jacked up and down his length faster than any hand but his own ever had, and he could see determination in her eyes.

“Do it, Percy!” she said. “Cover me in it! Shoot it all over me!”

Percy was going to do exactly that, but he would do it on his terms. He slapped her hand away, grabbed his own cock, and started slapping her face with it. Piper gasped at the cockslapping, but he could see how excited she was each time his cock hit her nose or rubbed against her cheek. He was starting to get a sense for Piper's sexual preferences and interests now. Aside perhaps from her blowjobs skills and ability to deepthroat his cock, what stood out was her submissiveness. She got off on the idea of him covering her in his cum, and she'd happily stroked his dick with that in mind. But him jerking his cock in front of her and slapping her face with it seemed to thrill her almost as much as it did him. Maybe that was why she was doing this with him. Maybe perfect Jason was just a little too perfect and proper, unwilling to get down and dirty with her like this.

Or maybe Percy was reading too much into it, and this was just how she was. In the end, it didn’t really matter. She sat in her lounge chair, eager to have him stroke his cock and slap her across the face with it, and he readily obliged. Percy grunted as he got closer to the end, and he watched Piper’s eyes follow his hand like she didn’t want to miss a second of it.

“Here it comes, slut,” he announced, rubbing her face in what they were doing. She was a slut, or she was acting like one today at least, and she moaned like she loved having it thrown in her face.

She soon had a lot more tossed in her face, or more to the point, shot all over it. Percy gripped his cock and took aim, firing his cum all over Piper’s face. He rained down a bunch across her forehead and down near her eyes before aiming lower for the second half of his orgasm, spraying semen in a thick diagonal line down her left cheek to her chin. The last few spurts of cum hit her lips, and Piper opened her mouth at the end and let him finish on her tongue.

Percy shook the last few drops off of his cock, and slapped it against Piper's right cheek to make sure he got it all. She smiled up at him brightly, wearing only her bikini bottoms and with her face covered in his cum, looking every inch the cheating slut she was.

His afternoon by the pool with Piper was off to a great start, but he wasn’t finished with her yet. If he had his way, he was going to have a lot more fun with Piper’s sexy, slutty body by the pool before anyone else showed up.

--

Piper’s bikini bottoms were bunched up in a ball, left behind on the chair she’d been lounging in. Though the lounge chair wasn’t made for fucking, Percy probably could have made it work. He’d elected to instead pull her to her feet and lean her up against the little table set up near the pool so he could fuck her. Her ass was right on the edge of the table, and her legs hung over the side. She kept her legs bent at the knees and spread apart, doing what she needed to do to get the deep dicking she evidently needed badly enough to let Percy nail her by the pool while her boyfriend was spending some time with his best friend. And Percy was the opportunist who exploited Piper’s horniness for his own benefit, standing in front of the table and pounding the cheating demigod hard enough to make her bare ass drag back and forth against the edge.

Percy was no better, of course. Piper was a cheating demigod, and so was he. He was happy with Annabeth, but no amount of happiness with his girlfriend could have gotten him to pull his cock out of Piper's tight cunt now that he was inside of it. If Percy had anything to say about it, this would be far from the last time he railed Piper McLean, no matter what happened with Annabeth. Fucking her was worth any consequences that might play out as a result of this, or at least that was how he felt at the moment. Maybe he would regret cheating on Annabeth after he was done.

Then again, maybe he wouldn't because Piper moaning loudly through every thrust was just about the sexiest thing he'd ever heard. And as far as lewd sights went, her tits bouncing right in front of him thanks to the pace of their fucking ranked at or near the very top as well. Her pretty face was still a mess, with his cum sticking to her skin. She hadn't made any effort to clean it off, and Percy didn't mention it. How she was going to deal with the mess later after it had dried onto her was her problem to figure out, and if she was too horny to think about it, it would be up to her to eventually come up with a solution. Neither of them was looking at things rationally right now, anyway. If they were, they probably wouldn't have been cheating on their respective partners by the pool, where anyone could have seen them if they happened to come back early.

Percy was not in any mood to kiss her. Even if her face and lips hadn't been covered in his cum, kissing would have felt out of place here. A kiss was a romantic gesture, or at least that was how he generally viewed them, and he did not have any romantic interest in Piper. His interest in her was purely physical. He wanted her body and nothing more. He wanted to fuck her, claim her, and mark her body as his. No, he wasn't going to kiss her. But he could use his mouth for much more enjoyable pursuits, such as bringing his head to her chest and sucking on her breasts. He sucked on her left tit, and his tongue rolled against her erect nipple. Piper groaned, and her hand ran through his dark hair. Her groan was shaky, and her fingers were trembling as if she were struggling to keep up with him. It made him wonder if she'd ever been fucked like this before. Maybe she was finding that, however her heart might feel, Percy was the demigod equipped to fuck and use her body the way it was designed to be used.

With every thrust of his hips, he did his best to drive his strength home to Piper. Fucking her tight body felt great, of course, but he was also out to prove a point. Whatever her reasons were for cheating on her boyfriend with him, Percy wanted to validate them. He might not love Piper or have any interest in a romantic relationship with her, but he did want her body. He knew he wasn’t going to be able to get enough of her after this, and he sought to leave her with that same need by the time he was done. Hearing her whimpers and moans and seeing her left hand clutching desperately to the edge of the table while he screwed her, Percy felt confident that he was well on his way to accomplishing his goal.

Percy switched from one breast to the other, sucking hard on her nipple while also putting even more into his hip thrusts. Piper was sliding so much under the force of his thrusts now that he moved to support her, putting his right arm underneath her thigh and holding her leg up while his left arm wrapped around her waist and held her lower back. Piper's butt was still sliding and dragging across the edge of the table, but she didn't slide as far now. Percy kept her leaning up against the table while he fucked her as hard as he'd ever fucked before. Annabeth didn't mind a quick pace, but there had never been this much raw lust behind any of Percy's encounters with his girlfriend. That he actually loved Annabeth might have had something to do with that. She was his lover, and he wanted to take care of her. With Piper, though, he took her not like a man enjoying time with the woman he loved but a man fucking the shit out of a sexy slut he'd picked up for a night of fun.

Being used roughly like this clearly worked for Piper, though, because she only got louder the longer he spent drilling her on the table. Frankly, she was moaning so loud now that he might have been afraid that Annabeth could hear her from her room on the second floor, even with all the doors and windows closed. This probably would have felt like a problem to him if he was thinking clearly, but slamming his cock into Piper's cunt and sucking on her breasts was all that Percy cared to focus on right now.

Her hand left his hair behind and held onto his shoulders instead, and her free leg wrapped around his body, kicking at his ass with her heel like she was begging him to fuck her even harder. Her moans made it impossible for her to ask with words, but he preferred her making her pleasure known by moaning and spurring him on with her bare foot anyway. Percy gave her nipple a little lash with his tongue, and he started rutting her so hard that it felt like a sure thing that she would have fallen if his arms weren’t supporting her and holding her up.

Percy didn’t bother to remove his mouth from her breast so he could announce his intention to cum inside of her when he felt the pressure building in his lower body. He didn’t see a reason to. They’d both made their choices long before this moment, and they were in too deep to turn back now. A cheating fuck on the table like this could only end one way, and that was with Percy emptying his balls inside of Piper’s cunt. Percy grunted around the nipple in his mouth as his cum began shooting out of his dick, filling Piper up and heading straight for her womb.

Piper gasped and stared at him with wide eyes, but any possibility that she might have been unhappy with his choice was eliminated seconds later. She let out her loudest moan yet, her hand moved from his shoulders up to hold onto the back of his neck, and her pussy squeezed his cock as she started cumming. Being creampied by a man who was decidedly not her boyfriend hadn’t caused Piper to have second thoughts about cheating with him. It pushed her over the edge and brought her to a massive climax. It was the kind of ecstatic cry that walls could not contain. Though none of their friends had ever mentioned it, at least to his knowledge, there were nights they’d gotten loud enough that no one would meet their eyes the next morning. After a handful of awkward mornings like that, Annabeth had taken proactive steps to try and keep her moans of ecstasy to a minimum.

Percy hadn’t ever heard Piper get loud enough to require such measures, at least not until then and there, with her moaning her pleasure out for anyone to hear as Percy filled her up and made her cum on the table by the pool. Percy thought his old rivalry with Jason Grace had been resolved and left in the past. Maybe it had lingered to a degree, though, because the idea that he’d likely just made Piper cum harder than her boyfriend ever had felt like a victory to him.

When he pulled out of her after he was done and watched his excess cum drip out of her to land on the table beneath her, Percy's victory was assured, and his mark was left. But maybe there was one more mark he could leave and one more hole he could claim.

--

Upon Percy’s suggestion that he wanted to fuck her ass, Piper informed him that she’d never taken it up the butt before. Before he could even begin to put together a plan on how he might be able to ease her fears, though, Piper rolled off of the table, dropped to her hands and knees on the ground, and wiggled her hips, inviting him to come and take her anal virginity.

Not even Percy in his current highly horny state was careless enough to immediately stick his dick in Piper's ass. He'd taken the time to prepare her, and they also laid a towel on the ground so she would have at least a moderate degree of comfort. There had also been a bit of care shown on his part when he first penetrated her, though that wasn't entirely selfless. He didn't want losing her anal virginity to be an unpleasant memory for Piper. He wanted taking his dick up her ass to be an enjoyable experience for her. If she enjoyed taking his dick up her ass, she would be more likely to spread her cheeks and offer her back door up to him again in the future.

He’d gone slowly at first, but there hadn’t been a need for Percy to hold back for long. Piper proved that her affinity for rough sex carried over to this as well.

“Fuck me!” she demanded only a few minutes after his dick became the first to penetrate her anus. “Fuck my ass, Percy!” He grinned and shrugged his shoulders. If she decided that she was ready for this, so be it. He moved his hands to her hips and started fucking her ass for real, thrusting into her and pulling back out, showing very little care despite this being the first time a dick had plunged into her rear like this.

She loved it. Piper was getting her ass pounded, and she loved it. She met his deep thrusts not with groans of discomfort but with moans of pleasure instead. She bunched up the towel beneath her fingers and moaned as Percy squeezed her hips and gave her the rough anal screw she wanted. If her boyfriend wasn't going to give it to her, Percy would happily step in and show Piper how great it could feel to have his dick buried in her butt.

The thrusts became too much for her to stay up on her hands and knees, so she let her arms rest by moving down to her elbows. Percy gave it to her even harder, moving one hand to the small of her back and slapping her ass with the other, taking full advantage of the fact that moving onto her elbows caused her butt to stick up higher in the air.

After a few minutes of pounding and spanking her while she had her butt up in the air, Piper let go and simply flopped down onto her belly on the towel, though she bent her legs at the knees. Percy adjusted his position, moving to squat over her with one foot and one knee planted on the towel to either side of her body. It was an adjustment, but he actually found it even easier to push his cock deep into her ass and keep up a good pace from this new position. He barely pulled back more than halfway before thrusting right back in, constantly sliding his cock into her tight depths and making her moan in the process. For a woman who'd never had anyone in her ass until a handful of minutes earlier, Piper was rapidly turning into a true buttslut, and Percy couldn't be happier about it. He was able to fuck her ass hard without needing to worry about how it felt for her because no matter how rough he got, Piper just kept moaning. She didn’t just take his cock up her ass; she savored the experience.

This couldn’t have gone any better for Percy. His hopes of being able to do this again in the future, and regularly at that, were growing by the second. How could Piper not be as hooked on this pleasure now as he was? Whether they loved each other or not was irrelevant. You didn’t need love to have great sex, and this was proof of that. Their hearts might not be connected, but their bodies were unarguably compatible.

Piper squealed into the towel as she came purely from the anal pounding, without any stimulation beyond that. He didn’t think she was deliberately trying to muffle her cries of pleasure. Rather, her face was pressed into the towel out of circumstance, driven there by the minutes of rough anal sex and the toll it had taken on her body. Percy didn’t care. He didn’t need her moans of pleasure to be heard by anyone but him. Her pleasure, like her body, was his alone to enjoy.

He wasn’t far behind her. Being inside that tight ass would have tested him no matter what, and the pace with which he had fucked it, at her insistence, guaranteed that his time in her previously virgin hole would be even shorter still. That wasn’t a concern, though. He’d already made his mark, taken Piper’s anal virginity, and even made her cum along the way. All that was left was for him to finish up.

Where he was going to cum wasn’t even a question. He’d been the first to stick his dick in her ass, and now he was going to become the first man to fill it with cum. He squeezed her round buttcheeks together and grunted as he blasted off inside of her rear, slapping her cheeks for good measure and marking her butt as his both inside and out. He did not get the feeling that Piper would object to him staking his claim on her butt. After all, she had been all too eager to offer it up to him despite informing him that no one had ever been inside of it before. And when his pace hadn't been to her liking, she'd urged him to fuck her ass harder. Piper was a cheating buttslut now—his cheating buttslut.

Percy had become a cheating bastard, too, but he felt no regret over that fact. If this was what cheating on his girlfriend felt like, his only regret was that he hadn't done it sooner. Then again, it wasn't like he'd planned this, and he still didn't really know why Piper had chosen to cheat with him so willingly. It felt like fate that he'd stumbled upon her in that sexy bikini and fate that she'd been as ready to cheat on her significant other as he had been.

The time had been right, and she'd looked too damn good for him to ignore. Percy already had respect for how pretty Piper was and how good a woman's body could look in a two-piece. Together, the two made an irresistible combination.

--

Annabeth waited until they were both asleep before removing her baseball cap and becoming visible again.

She still wasn't sure why she'd felt possessed to follow those obviously erotic noises. When she'd discovered who was bringing those noises out of Piper, she should have been furious with them both. She should have smacked some sense into Seaweed Brain and called out Piper for being possibly the worst friend a girl could ask for.

Instead, she stood and watched, invisible and unable to tear her eyes away. It was not anger she felt as she watched her boyfriend fuck the hell out of one of her best friends. It was arousal. She’d arrived right around the time that Percy was starting to fuck Piper on the table, and she’d seen him cum inside of her and fuck her ass, despite Piper saying that she’d been an anal virgin before that. She’d stood and watched it all, and taboo as it was, it had been the hottest thing she’d ever seen.

But how was she to let them know that she’d seen everything? How was she to try and arrange for a repeat performance of voyeurism—or maybe next time, she could even join in?