Crystal

Your eyes meet hers again, and the corners of your mouth turn up into a grin. You crawl over next to Crystal, moving slowly, deliberately, taking your time. With two of your fingers, you walk your right hand from her feet up to her calves, then higher up her thigh, poking her skin as you go. The muscles in her legs quiver lightly under your touch, and her breathing grows ragged.

"And what would you want me to do?" You ask casually, as your fingers come to rest just inches away from her crotch. Her face flushes redder, and her tongue darts out to lick her lips. Behind her, Lisa kisses Crystal's cheek gently, nuzzling her encouragingly.

"Well, I..." Crystal stammers, trying to put her thoughts into words. Her heart pounds in her chest, her hands fidgeting. "I was wondering... if you could... um..." She groans softly, bites her lip nervously, then blurts it out all in one go. "If you could fuck my ass? Please? I'm dying to know what it's like!"

She covers her crimson face with her hands in embarrassment, her blush going all the way down her neck to her shoulders. Next to her, Lisa is frozen in place, staring at you with wide eyes, waiting for your reaction.

"... Oh." You reply dumbfounded, not really knowing what else to say.

You can guess where this comes from. The boy in summer camp had requested to play the giving role in the relationship, which Crystal had backed out of. But something about bottoming must have stuck with her.

"I'm not a deviant or anything!" Crystal squeaks, still covering her face with both hands. "I love to fuck boys' asses, alright?!" She exclaims quickly, somehow turning even redder. "It's just... I want to try it the other way around, once! Just this once!"

Lisa stares at you, waiting for you to react. She is clearly taken aback by this request, too, especially considering that she grew up before the Internet, which gives validation to literally any fetish imaginable, thus causing its users to explore their sexuality more freely. You sort through your feelings quickly, again doing your best to zone out the external influence of society on your decisions. Alright, so Crystal has a kink, and wants to try something new, which is... fine. And it can't hurt to try, right?

"Okay," you finally reply, giving her a grin which you hope looks confident. "Let's do it."

Crystal peeks out from behind her hands, looking at you with an excited expression. "Really?!"

You nod firmly. "Yes. Really."

A huge smile spreads across her lips, and her hands fall from her face as she beams at you. Lisa looks back and forth between the two of you, still speechless.

"Awesome! Thank you so much, Doug!" Crystal exclaims happily, scooting closer to you and wrapping her arms around you tightly. She plants a wet kiss on your cheek before pulling back again, grinning up at you. "Can we start now? Please? Before I change my mind!" She asks eagerly.

You chuckle softly, hugging her back and looking into her eyes intently. "Just a moment. I haven't done this before, but I'm pretty sure I need to get rid of my chastity cage first." You give her a wink.

"Oh. Okay." Crystal murmurs, her cheeks turning pink again. She pulls her hands away from you slowly, giving you some space as you crawl over to your bedside table, pull out the key, unlock the cage, and remove it. There's no particular feeling of relief when you do so; it's comfy, and your penis usually stays soft inside of it. But there is an odd sense of excitement as you prepare to venture into sex from a woman's perspective.

Turning around, you see Crystal's trembling butt sticking up in the air, her face pressed into the mattress. Lisa has taken a big bottle of lube out of her bedside table - something that every woman keeps close to her bed - and is currently gently slathering it liberally over Crystal's asshole, whispering gentle encouragements to her. "It's all about relaxing, baby," she purrs as she spreads the clear gel around her daughter's puckered sphincter. "Don't try to outdo Doug and you'll be fine, okay?"

Muffled through the mattress, you can hear something that sounds like "Uwuwuwuwuw..."

Turning to you, Lisa motions you over to her. "Come here, sweetie," she begins, "I think she's ready. I don't think I need to tell this to a man, but be gentle with her, you hear?"

You nod, scooch over to Lisa, and with her help, she guides you into position behind Crystal. Her lube-coated hand reaches around, wraps itself around your dick, and starts stroking you, coating you thoroughly in the slippery liquid. The sensation of another person's touch on your member feels foreign, exciting, and it brings your blood flowing rapidly to your cock. You groan quietly, closing your eyes as she touches you intimately.

Before you, Crystal's rump sticks up into the air, her glistening asshole staring right at you, begging to be penetrated. Her cock is half-erect, hanging down low alongside her balls, squeezed between her thighs. And there, in the middle, you see her glistening vagina, a woman's most sacred place. Where children are made, after man and woman switch their roles for one night.

"Alright, easy now," Lisa whispers to you gently as she aims your fully erect cock towards Crystal's butthole. You lean forward carefully, pressing the tip of your shaft against her sensitive skin, feeling it twitch under your touch. Crystal stiffens up as you make contact, then relaxes again slowly. The feeling is... different. Not bad, just new.

With gentle pressure, you begin to push. Crystal groans loudly at the sensation, gritting her teeth. Lisa leans down close, placing her palm gently on her daughter's back, and caressing her shoulder lightly. "Just breathe deeply, Crystal. Relax as much as you can. You're doing great!"

"Ooohh..." Crystal groans, turning her head towards Lisa, taking deep breaths and trying to comply. "Ohmygod..."

Slowly, steadily, you push forwards, watching closely as your cockhead stretches her firm opening. You feel resistance from her muscles, clamping down around the tip of your dick, and you stop every now and then to let Crystal adjust. Eventually, her sphincter gives way, allowing you inside. With a pop, your cock slips into her ass, entering her body completely. The sensation is incredibly hot and tight, clamping down on your dick, almost hurting you. You gasp softly, pausing for a moment.

"Ahhhnnnghhh! Ahh fuck!" Crystal cries out, burying her face in the mattress again. Her toes curl up instantly, and her ass twitches repeatedly, clenching around your rod. She breathes raggedly, gasping for air desperately. Her hands grasp the sheets in two solid fists, giving her some resemblance of support. "Fuck... fuckfuckfuck... that's... aaaah..."

Lisa kisses her cheek tenderly, rubbing her back reassuringly. "You're doing wonderful, baby," Lisa murmurs, her voice heavy with lust. Her other hand reaches underneath her daughter, and begins massaging her breasts slowly, pinching her nipples gently. "Let him in, nice and easy."

Your heart is thundering in your chest, and you have to focus on keeping your breathing steady as you wait for Crystal to adjust. The tight insides of her rectum massage your cock wonderfully, stroking it like a pair of soft hands. Eventually, she relaxes again, and you start thrusting gently.

Her anus feels snug and pleasant, and you move slowly, sliding deeper inside with each stroke, pushing more of yourself into her. Her insides are incredibly soft, silky smooth, and warm. It's a wholly unfamiliar experience, but there's something about it that makes your blood boil.

"This is amazing," you mutter, gazing down at the two of them. "It feels so good..."

Lisa looks up at you and gives you a knowing smirk. "Doesn't it just?"

Your sister moans softly as you slowly pump her petite butt, your hips making wet squelching noises as you go. The lubrication is working great, letting you slide in easily. Your cock throbs as her sphincter squeezes it tightly, milking it expertly. Every nerve in your body seems to be alive with pleasure, sending delicious chills up your spine into your brain.

Then, suddenly, Crystal starts to move her hips backwards, meeting your thrusts halfway. You gasp at the unexpected sensation, and she lets out a muffled groan. Her ass flexes around your cock, rippling slightly, pulling you in even further. You pause momentarily, not wanting to hurt her, but she pushes back against you impatiently.

"Give her all you've got, sweetie," Lisa encourages you quietly. "She is ready."

"Unnngghh..." You groan, grabbing Crystal's waist with both hands. She whimpers loudly as you slam your hips forward, bottoming out completely in one swift movement. Your balls slap against her dripping pussy as you grind against her, holding yourself pressed against her backside firmly. Then, you start to move, fucking her with quick, hard strokes.

"Ohmygod! Ohmygodohmygodyes!" Crystal babbles mindlessly, working her ass back to meet your thrusts, taking you even deeper.

The muscles in your loins burn with exertion as you fuck her ass, driving your dick deep into her bowels again and again, listening to the lewd squelch of your bodies slapping together. She is incredibly tight, and feels absolutely wonderful, sucking you in like a vice. Her anus clamps around your shaft repeatedly, squeezing you so wonderfully, you know you won't last long like this.

Lisa watches the two of you intently as you piston your meat into her daughter's rectum. "How does it feel? Are you okay?" She asks, still kneading Crystal's breasts gently, massaging her sensitive nipples.

"Aahhh! Yes!" Crystal groans, lifting her head up again, her messy hair falling into her face. "I'm... AAAH... I'm almost... gonna..." Her words trail off as you thrust faster and faster, your own breaths coming in short gasps now.

"Me too," you pant, holding onto her waist for your dear life as you plow into her ass recklessly. Tingles of pleasure shoot up from your groin to the base of your spine with every impact, and you can already tell that you're going to cum soon. "Unnfff... I'm close..."

"Good girl," Lisa replies, then reaches underneath Crystal's body with her left arm and grips her cock. "Don't hold back, baby. Let it go."

With a loud, long groan, Crystal explodes, her buttcheeks flexing around your shaft. You grunt loudly at the sensation of her anus rippling around you, milking your member desperately as she orgasms.

"Aaaaarrrgggghhh!" She cries out, arching her back sharply. "Ooooohhh fuck! Yesyesyesyesyes!!!"

Your own orgasm follows immediately after hers, triggered by the feeling of her tight asshole contracting rhythmically around your shaft. With a powerful thrust, you bury yourself inside her deeply, grunting loudly as you pump a load of spunk deep into her bowels. You remain there for a moment, pressing your crotch against her ass, enjoying the sensation of your cock twitching inside of her as you empty your balls into her hungry hole. The muscles in your loins burn with exhaustion as you pull back out slowly, watching your cream ooze out of her gaping butthole.

Lisa is grinning from ear to ear as she watches the two of you recover, panting heavily. "Well that was new," she chuckles softly, kissing Crystal's cheek. "How are you doing, honey? Did you enjoy it?"

"Uh-huh..." Crystal mutters dreamily, her head buried in the mattress again. Her hands still grip the sheets tightly as she comes down from her high, trembling slightly. Her cum pools on the sheets between her knees, and her lower thighs are soaked with her load, as well.

"How about you, Doug? How did it feel?" Lisa asks, turning her attention towards you.

You smile at her tiredly. "I didn't realize how exhausting the active part is. I'll be sore tomorrow for sure." You chuckle weakly, glancing at Crystal. "But yeah... it felt amazing. I loved it. Thank you for this, Crystal."

She smiles back at you tiredly. "Same to you, Doug."

From your side, you hear Sarah's voice go: "What in the bloody fucking hell just happened here?"