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so crazy it just might work

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It starts with Sally insisting on taking Casey along on their date, because Casey is “heartbroken” about Max and that’s his problem somehow.


“I think we should admit our feelings tonight,” she says.


Aghast and, quite frankly, confused, Derek responds, “First of all, I don’t do feelings. Second of all, you already know how I feel about you.”


Patient as always, Sally smiles. “I meant our feelings for Casey.”


Derek pauses, his face hopefully translating the horror he feels on the inside (and it is horror, mind you, not anything else). “Our what now?!”


She keeps looking at him expectantly, like if she waits long enough he’ll eventually clue in on what the hell she’s talking about.


He does not.


“OUR feelings?!” Derek squeaks.



Sally, who likes to remind everyone that she is nineteen - therefore older than them and can now buy her own alcohol (Derek tolerates it, because he benefits from this), brings along a bottle of Jack Daniels on their “date”. She pulls it out of her purse and shows it off smugly before they enter the theatre.


“You can’t bring that in there!” Casey exclaims, ever the party pooper.


Derek snorts. “Live a little dangerously, Space Case.”


Sally mixes rum in a large coke they share while watching the movie. Derek only takes a few sips because he’s not that dumb and won’t get drunk when he’s supposed to be driving.


When he goes to wrap his arm around Sally’s shoulders, he realizes that she’s snuggled away from him and into Casey. As if he isn’t there at all.


Derek definitely isn’t sulking.



When the movie is over, Casey and Sally are apparently tipsy enough that they need some help walking in a straight line to the car. Derek has to walk with both of them hugging his sides so they don’t look stupid, their warm breaths tingling against his neck as they giggle and blurt out dumb secrets at each other.


Sally takes the backseat with Casey, and Derek starts the car with a sigh, resigning himself to being ignored for the rest of the night. Except, that’s when things start to get… interesting.


“Casey, you are so pretty,” Sally says. A quick look into the rearview mirror confirms that his girlfriend’s hands are all over his step-sister’s body, and that’s totally fine with Derek, really. He wouldn’t like to be included or anything like that. “Derek, isn’t Casey pretty?”


Her voice startles him out of his careful maneuver out of the parking lot. “Um,” Derek utters. He’s pretty sure any shitty comment will get him further denied and ostracized, so he goes for the safe, non-committal answer. “Sure.”


Sally moves on like she couldn’t care less about his answer. “I want to kiss her,” she says, “can I kiss her?”


Derek holds more tightly onto the steering wheel, mindful of the ditch he’s not looking forward to crashing into. “Sure,” he responds through gritted teeth, his eyes flicking to the mirror once more.


Turning to Casey, Sally bites her lip and asks: “Can I kiss you?”


Casey, dumbstruck, nods and says: “Okay.”


They kiss softly at first, and Derek thinks it’s only going to last a couple of seconds, but then they are laughing in the backseat and the kissing turns into making out, and Derek has to stop the car. He has to, or he’ll die, most likely. His dumb teenage boy brain figures if this is happening, well, maybe he’ll get lucky. So he drives them to the popular make out spot and parks. He doesn’t move.


The sounds coming from the backseat are indecent. Derek’s blood isn’t flooding in the direction of his brain anymore.


In between all the loud as hell smooching, Sally finds her breath long enough to call out to him. “Derek? Aren’t you coming?”


Derek thinks this is the best and worst day of his life.




“Come on, Der-eeeek,” Casey whines.


He knows she’s not that drunk. She just can’t be.


“I didn’t have as much to drink as you two did.”


“I think we can fix that,” Sally points out, sultry and wicked. She wiggles the bottle of Jack towards him between the seats. When he goes to take it, she wrenches it away. “Nuh uh,” she says, “the party is back here.”


Next thing he knows she is grabbing at him and forcing him into the backseat. Casey, giggling like an innocent, but smiling like ultimate evil, is helping Sally pulling him at the back between them.


He finds himself in one of his dreams he remembers having, and pinches himself to make sure he’s really awake - or, alive.


Sally is holding the liquor up for him to drink, and his hot step sister is clawing at his chest until his mouth is free for her to swoop in. Then she’s kissing him, and he grabs the back of her hair and kisses back, because he’s not a fucking idiot.


Casey’s tongue is in his mouth and she’s straddling one of his thighs while Sally is leaving hickeys down his neck, and he’s pretty sure he’s going to wake up any moment now.


He doesn’t know what to do with his hands, he has one arm looped around Sally’s waist, his other hand is sneaking under Casey’s shirt to squeeze her side.


The car is filled with girly moans and his heavy breathing. He’s pretty sure making out with his girlfriend and his step-sister is the hottest thing to ever happen to him.


Then Sally’s hand is on his crotch, caressing his erection over his jeans. He stutters obviously enough for Casey to pull back curiously to see what’s happening.


Derek is not strong enough of a man to stop Sally’s hand, so he just lets his head fall against the back of the seat while Casey watches Sally rub him up and down.


She’s been acting tough so far but he can tell by the blush on her cheeks that this is going much farther than she anticipated.


He wants to say something, to reassure her that it’s okay, she doesn’t have to do anything she doesn’t want to do. All that comes out of his lips is a whisper of her name, before Sally is kissing her.


Casey seems to snap out of it and grabs both sides of Sally’s face as they kiss ravenously. Sally’s hand is still playing with his dick while the girls kiss above him. Derek thanks his lucky star that he’s not prone to premature reactions because he really doesn’t want this to stop.


He watches them in fascination, the small glimpses of tongues poking into each other’s mouth, little sighs when their lips part for barely one second. Sally’s free hand strays between Casey’s thighs to cup her underneath her skirt, and Casey makes this cute, surprised sound that Derek wants to hear again. He kind of wants to jump back in the action at this point, so he reaches out to meet Sally’s hand under Casey’s skirt, insanely pleased to find soaked panties. The fact that Casey is as turned on as he is by all of this makes him burn inside. He wants to hear her moan like Sally does when he touches her like this. He kind of wants to hear how they would sound, crying out in pleasure together.


His other hand goes for Sally, but meets denim, making him groan in displeasure. Sally turns her attention on him with a devious smirk and she kisses him heatedly, her hand leaving the shelter between Casey’s thighs in order to undo his belt and pants. Left on their own to do as they please, his fingers pressed against Casey’s heated center tug her panties aside to rub her directly, fingertips pressing into her folds and thumb finding her clit. Casey mewls, a sound so divine his eyes snap open so he doesn’t miss it coming out of her lips. She tosses her head back and grabs onto his shoulder for support.


Sally has his dick out by now and she strokes him in time with the movements of her tongue against his. It feels so good he’s not sure how long he will last. He doesn’t want to come early in Sally’s hand and ruin everything, so he focuses on what he’s doing to Casey, trying to keep one eye open so he doesn’t miss Casey licking her lips while she moves her hips to rub herself against his palm.


He’d expect there to be some talking besides Casey’s hot whispers of “oh my god” breathed against his neck. But there is no need for words or directions, everyone’s movements flowing as well as if they were rehearsed.


Leaving his mouth, Sally trails kisses down his throat, gently sucks on his Adam’s apple and nips at his collar bone. She shoots him another pleased smirk as she lowers herself farther and wraps her lips around the tip of his cock.


He utters a strangled “Fuck!” at the feeling of her hot mouth around him, her tongue licking off the precum leaking from his excitement.


In the heat of the moment, he grabs the back of Casey’s head and smashes their mouths together. She hisses from him pulling on her hair but returns the kiss. It’s hard and rough, their teeth clashing against each other. Casey’s letting out little cries into his mouth as he dips two fingers inside of her, pumping increasingly harder and faster as Sally sucks him off. Casey is out of breath and pulls away as she pants and moans her pleasure.


“Oh my god,” Casey squeaks and she wraps both arms around his neck, holding onto him like a lifeline, hugging his head tightly against her chest.


Sally has him deep at the back of her throat and it’s getting so hot inside the car the windows are fogging over. He groans out a few curses and indulges in the need to bite into something, the closest thing available being Casey’s breast.


As he bites into her breast, Casey cries out louder, echoes of her laboured breathing mingling with the squishing of his fingers fucking her. Casey’s leaking down into his palm and he wants to know what it tastes like without having to stop her making those sounds.


Repositioning and slowly sliding lower into the seat, he pulls his fingers out of her, to her audible chagrin. Smirking, he takes hold of her hips and says, “Come here.”


Her confusion only lasts a moment before he’s pulling her hips up, to meet his face. She lets him move her, he wants to say obediently, even as he practically shoves her into the back window in his eagerness to acquaint his face with her pussy.


How satisfying it is though, the taste and smell of her against his face and her moaning as his tongue flicks over her clit. He is so hungry he wants to devour her. His own pleasure is building up in his lower region, making him ravenous to latch his mouth on her. He takes her whole in his mouth, pressing into her and letting the whole surface of his tongue lap at her inside and out. Her legs are shaking as she cries, “oh, yes, Derek, yes, oh god.”


It’s getting so hot he feels like he is boiling inside. He is not quite satisfied though because someone isn’t moaning and that won’t do. As if on cue Sally pulls away from his cock with a pop, licking her lips as she strokes him with a determined hand.


He keeps Casey pressed against him, squeezing her ass firmly with one hand, and gestures towards Sally with the other. He means for her to put her crotch against his hand or something but she surges closer to press against Casey’s back and leave little nips on her thighs.


“Sally,” Derek pleads between licks, “c’mere.” He gestures with his hand once more.


Her breath blows against his forehead as she rests her chin on Casey’s thigh. “I want to watch you fuck her.”


He has to pull his mouth away to breathe and take that in. Casey stays quiet in response to this, and he decides to slap her ass to snap her out of it, making her squeal. “It’s up to you.” He looks up and meets her glassy blue eyes. “You wanna come on my mouth or on my dick?”


Casey stares at him, blinking and biting her bottom lip. Fuck, she looks so innocent and sexy it’s driving him crazy.


“It’s not your first time, is it?” he presses, eager to resume their activity as his dick throbs for attention.


She shakes her head shyly. He gets the feeling if it’s not her first time, it’s pretty damn close. It’s probably been all boring and vanilla up until now.


Sally is rubbing her face against Casey’s side like a cat for attention. “We’ll take good care of you,” she assures honestly, then smiles, “like a princess.”


The nickname makes Derek shiver almost as much as it does Casey and the look on her face tells him that she’s on board, thank fuck.


Fucking Casey is a fantasy that always seemed so farfetched he hasn’t let himself entertain the possibility. Now that it’s about to happen, he feels himself getting unhinged.


It’s not the perfect circumstances either. The back of the Prince is small and crowded. He’s not sure how that’s all gonna happen with the three of them squeezed in the back, or what Sally’s going to do while she watches him fuck his step sister - which the thought of it turning her on is turning him on even more.


“Fuck, okay,” Derek practically growls. “Get me a rubber?”


While Sally happily reaches for a condom in the glove compartment, Derek pulls Casey off him until she’s kneeling beside him. He sits up, doesn’t resist stroking himself because if he doesn’t he might explode, but resumes petting Casey’s pussy gently with his free hand. A soft sigh escapes her lips and her eyes flutter closed. She is way too adorable. He hates the effect she has on him. Just the sight of her.


He leans forward and whispers against the corner of her mouth, “You sure you want this?”


She nods so quickly and eagerly, it makes him laugh and want to kiss her, so he leans in and captures her mouth in another heated kiss. Sally comes back and sits in his lap with the bottle of Jack at her lips. When he separates from Casey, she offers him a sip. He lets the liquor roll off his tongue slowly as Sally gives Casey the bottle. Casey holds it to her mouth with both hands like a baby holding a nursing bottle. She grimaces and hands it back to Sally who drops it in the front seat before jumping in to kiss her again.


Derek, once again, finds himself underneath both of his girls making out, with the fingers of one hand dipping into Casey’s wet cunt and the other wrapped around his dick. He notices that Sally has the condom hostage in one of her hands. Since she seems to know what she wants, he asks, “so, how are we doing this?”


She breaks off her kiss with Casey to look at him. “Lie down.”


She eases herself off him to allow him space to move. It’s a bit awkward, with Sally holding herself between the two front seats and Casey scooting over while he stretches out.


“Wait,” Casey says before he’s fully settled. She reaches for the lapels of his leather jacket. “Take it off.”


He goes to take it off but thinks better of it before it’s slipped off his elbows. “You take yours off first.”


She’s not wearing a jacket, but he eyes her tight fitting long sleeved shirt pointedly enough for her to know he means business. She only hesitates a moment before pulling it over her head and throwing it at the front of the car. Her bra clad chest is revealed to him in all its glory, a sight he has prayed many deities to one day be worthy of (bikinis don’t count - they don’t, because they’re not made of black lace and holding her breasts up together so tight they look like they might spill out). Fuck, she’s so hot.


“Sally, too,” he says, out of breath all of a sudden. Sally takes her shirt off without complaint and he removes his jacket while she moves on to removing her pants. She almost falls backwards between the seats, but catches herself on time, laughing as she pulls herself back with Casey’s help. They both laugh and smile at each other, and they kiss again and Derek knows he is the luckiest fucker on this planet to be even allowed to look at these two goddesses, his beautiful girlfriend and damn tempting step-sister who sleeps in the room next to his, in a glorious state of undress and kissing with tongue like they’ve been pining for each other for ages. Maybe they have, he thinks idly.


He relaxes back into the seat and strokes himself lazily while he waits for them to pay attention to him again. It takes a moment. “Someone gonna take care of me or do I have to do it myself?”


Sally giggles against Casey’s mouth and throws the condom his way, a clear signal to put it on, which he readily does.


Ready and covered, he looks on as Sally gently nips at Casey’s bottom lip and their foreheads press together. They’re whispering things Derek can’t hear, which makes him feel somewhat left out but also weirdly warm inside, because the way they look and smile at each other is beautiful, and who cares if they share girly secrets when they’re in their bras and willing to fuck him silly.


He’s got something really good here. And it’s not just the otherworldly experience of having an impromptu threesome with the only two girls to have succeeded in turning his world upside down (though that’s pretty cool too), it’s way more than that. It’s deeper than that.


There are things stirring inside of him, like broken pieces of himself moving around and snapping back into place.


He feels something more strongly than he has ever felt before, something bigger than he can describe. But he feels it. He can practically touch it, the answer is right there, in the way Sally’s green eyes meet Casey’s blues with the same longing they meet his, the way they all fit together perfectly without having to say a thing.


It’s in the way he reaches blindly for the nearest body part to hold on to like it’s the only thing that can keep him above water, and his hand somehow finds Casey’s, wraps around it and tugs until she falls forward, flat on her stomach on top of him. He needs to kiss her now or he’ll drown. He kisses her hard and thorough, both of his hands tangling in her hair, pulling against knots. She groans and moans, in pain and thrilled satisfaction, her hips are moving on top of his deliciously - delightful torture. He feels split in half, one half now filled with the feeling of Casey on top of him, her smell surrounding him, and the other half wonders where did Sally go. There’s always a part of himself yearning for Sally when she’s not there, like the sight of her can heal all his pains, like he can find all the answers tucked under her soft skin.


And like a miracle she materializes next to him, she’s still partially nudged between the front seats and leaning/crouching next to them, and he vaguely thinks that just can’t be comfortable, but she’s not complaining. His mouth leaves Casey’s to meet Sally’s, one of his hands frees itself from brown locks to tug gently on blonde. He keeps Casey close, not done with her yet -if ever- only allowing her head to move enough to continue kissing the side of his neck while he fills the other half inside of him with Sally’s kisses. Where once he was empty, he is now filled up twice over. If he was a sap, he’d say something about his heart expanding, or his soul being finally at peace. But he’s not a sap. He isn’t. It just happens that his heart beats faster when he’s around both of them, and maybe there’s a sense of deep harmony vibrating around him when they’re close.


Derek’s senses are overwhelmed with smells and tastes so sweet he might just get a sugar high. He gets peaches and cream on Sally’s lips, and strawberry and vanilla on Casey’s skin. There will never be a dessert good enough to measure up to this.


He wants to burrow himself into it, the sweetness, the warmth.


He wants to be wrapped up in it, swallowed by it.


Fuck, his cock is just aching to be buried in that wet heat, so close, just within reach, throbbing right above him.


Casey’s hips are still moving in that slow, torturous way on top of his, driving him insane.


A desperate noise escapes his throat, his hips buckle up of their own accord, searching in vain for more friction. Then he’s calling her name without meaning to, “Casey”, he says in hopes that she will take pity on him, mere mortal, and let him enter the sanctity of her body.


She nods frantically, face hidden in the crook of his neck. His eyes roll in the back of his skull, almost overwhelmed by the anticipation, and open again at the sound of Sally’s voice in his ear. “Do it.”


He slips right in, wet folds welcoming him home like he belongs, and he sighs in relief, utter and complete joy at finally meeting his new -other- favourite place.


Casey pushes down on him, making the cutest sounds he’s ever heard coming from her. He feels her teeth dragging down his throat, her hands clenched around fistfuls of his shirt.


He wants to get lost, right here in this moment, inside Casey, falling deep into Sally’s sea-green eyes. He pulls Sally in for another kiss, seeking all the taste he can find in the confines of her mouth. His hips are moving slowly, with Casey’s sinking down to meet his gentle thrusts.


While this moment is perfect on its own, Derek really wishes they were in a bed, where he would have plenty of space to flip them around at will and look down at the two beauties under him, instead of the back of his tiny car.


He needs Sally closer, somehow, if she could squeeze in between them or under them or on top of them, at this point they could all be melting together, he doesn’t care.


Casey’s soft cries are filling his ears, leaving him in no hurry to go faster. He sees no sense in rushing, wanting to stretch and milk the moment for all it’s worth. If there was a way for him to be inside Casey and Sally simultaneously, fuck, that would just be outrageously satisfying. At this point, there’s only one way he figures he can sort of make that happen.


Pushing Casey’s hair out of the way, Derek presses his lips against the shell of her ear, “sit up, baby girl.” She does reluctantly, hair falling around them like a curtain, and meets his eyes as she pulls back. He takes the opportunity to steal one quick kiss before helping her back to sit on her haunches. She moans a little bit as she sinks down on him again. In this new angle it’s like he reaches deeper, in new, yet unexplored territory. He guides her hips back and forth a little, muttering gentle encouragements, “that’s it, just like that”, lets his hands wander up her body to cup and squeeze her breasts, to her delight, it seems, as it encourages her to move a little faster, moaning and throwing her head back. “That’s it, baby.”


His attention turns to Sally, looking radiant and flushed, and he grabs whatever part of her he can reach in order to pull her forward. “Come on,” he cajoles, “wanna sit on my face?” He bites his lip as he watches her eyes light up. There’s no way of explaining how much he likes the way Sally seems so comfortable around him. She has never shied away from his gaze, tried to hide any new part of her he’s exposed, or been reluctant to tell him what she wants. It makes him feel good, like she knows she can trust him and that he’ll always give her anything she wants. Including eating her out whenever she wants. She likes that very much, lucky for him. She straddles his head without hesitation, and he quickly sets to work, lapping and nipping gently at her underwear. Sally giggles, the way she does to show she is pleased with what he’s doing. He smiles up at her because he can’t help it, feeling like a lovesick idiot, before pushing her panties to the side and eating her out heartily.


There’s a girl on his face, another on his dick, he really doesn’t think life gets better than this. And they’re not just any girls either, which he absolutely does not take for granted. These two girls are his -not in a weird possessive way- they are his the way he is theirs, the way they belong together and to each other. His heart, his mind, his whole life will always be full of them.


It’s exciting and devastating. It’s every guy’s wet dream but it’s Derek’s destiny. He knows it’s not just a night of quick fun. This night will stay with him and haunt him and energize him for the rest of time.


And somehow, that does not make him anxious at all. He has already made his peace with it, accepted his fate.


If this is what doomed is like, he wants in, he’ll take the plunge. No looking back.


No looking away, either.


He is seriously mesmerized by the vision in front of him. Sally’s writhing against his mouth, her body undulating with every roll of her hips, her long, shiny blonde hair tossed to the side. He can’t see Casey but he can feel her, hot and tight around his cock, both of her hands grounded on his chest as she impales herself on him over and over.


His climax is approaching again, building like a knot at the pit of his stomach. He knows he can make Sally come with his mouth if he does it just right. If her frantic grinding and the way she’s cooing over him is any indication, she’s pretty close too. His hips keep meeting Casey’s thrusts faster and harder, and every time he hits deeper, she cries louder - she is delightfully loud, and her screams of “ah, Der-ek!” blend together with Sally’s “oh my god, yes”, and it’s music to his ears, like a choir of angels singing his praises.


It takes everything he has to hold back just a little longer, but he knows he has to, it will be worth a thousand blue balls if his girls are happy and satisfied by the end of the night - and maybe, maybe, he’ll get to do this again after.


Sally’s thighs are shaking and squeezing his face, which Derek takes as his cue to kick it up, push in deeper and bury his tongue as deep as he can. She moans and almost doubles over, laughing and pleading, “Derek, oh, please, Derek.” For the coup de grâce, he brings his fingers into play. He only needs two, dipping in and petting just the right spot inside that will make Sally unravel and fall apart around him. He fucks his fingers into her, hitting her sensitive spot while unleashing his tongue on her clit, flicking it back and forth vigorously until Sally’s whole body shudders, her hips stutter and she lets out a long strangled cry as she comes for him. Spent, she wiggles herself down his body before falling limp across his chest, letting out a joyful giggle. “Oh my god.”


Derek now has a full view of Casey riding his dick, looking even more flushed, sweaty and fucked than he last saw her, and he almost comes on the spot. Her hair is a big mess, from his messing with it earlier and probably her pushing it back out of her face. His girlfriend is nuzzling his chest and his step sister is still riding his dick, and he really needs to do something about his impending release. He has more freedom of his movements now so he can reach Casey’s front and rub her clit. The way she looks at him, imploring, with her eyes glazed over, her lips pressed together into a thin line to try and hold back her moans is too hot to handle. He wants -needs- to hear her climax.


“Come on, Case,” he goads, increasing the pressure of his thumb against her clit. She’s practically sobbing. “Take what you need.”


She nods, oh so docile and keen to please, and sits up straighter, holding herself against the backseat on one side and the headrest of the backseat on the other. She jumps up and down, faster, lets herself fall down harder, and whines, and whines and Derek. Taking pity on her, he rubs her harder. Her hand is in her hair again, pulling at it like she’s going out of her mind, are those - are those tears? Is she crying? Holy shit - holy shit. She hops up and down on his dick, moaning like a wanton woman, and she’s crying. He really needs her to come right now, or he’ll come first and then it’s all over.


Thankfully, not one minute later, she’s sinking down on him one more time, and lets out a long high pitched moan. She’s looking down at his hand as he mistreats her poor little clit, legs shaking until his abuse becomes too much, and closes her thighs around his hand.


He pulls his hand away, gently pushing her thighs apart again and pulls her forward. She falls with her chest against Sally’s back, and he holds her hips down just a little longer, indulging in a few more thrusts -inside her is a lovely place- until reaching his own shuddering orgasm.


He sinks into her one last time with a guttural groan as he ejaculates, pumping every last drop inside of her, and pulls out, his limbs giving in to the buzzing pleasure coursing through him. He feels lighter, relieved, and goddamn pleased with himself.


Casey and Sally are stacked on top of each other, on top of him, and he barely feels their cumulative weight more than a pile of feathers.


Sally is looking up at him with a smile on her face like she knows something he doesn’t. She probably does. She always does. He leans down to kiss her softly.


He can see Casey’s eyelashes flutter but she’s looking away, her cheek pressed between Sally’s shoulder blades. His hand comes up to play with her hair as he calls out to her softly. “Case.”


She looks up and reveals a dazed smile on her lips, and Derek finds himself smiling back.



Later, they sneak Sally in while everyone is asleep. Derek is about to doze off when he hears his door crack open and close softly, then little feet shuffling towards his bed. He turns to find Casey standing there, playing with the bottom of her pink teddy bear pyjama top. It’s a damn too cute PJ for the sex goddess he’s witnessed earlier, but that’s just Casey, always surprising him and making his insides melt.


Before she can say anything, he pulls part of the cover aside, inviting her in. She climbs in shyly, trying to keep her distance for some reason. Derek has none of it. He wraps his arms around her shoulders and pulls her close, and she sighs, happily cocooning under the blanket and into his side.


There’s barely enough space for the three of them in Derek’s double bed. But they don’t mind.