Collaborative sex stories let us write the plot together

(Her Secret Fantasy, continued by Xdot...)

“How about my step-sister Amy?” you suggest.

Your girlfriend just stares at you. You can’t read her expression.

“So? What do you think?”

“You want to fuck your step-sister?”

You sheepishly say “yes” and shrug. She probably thinks it’s weird. It probably is a little weird. You’re just about to tell her to forget about it when she kisses your lips.

“That would be the hottest thing ever,” Rachel whispers into your ear. She strokes your dick till it’s erect, then mounts it and rides you till you both cum. Then she lies down on top of you, tired and sweaty and smiling. The next weekend, you two decide to invite Amy over. You tell her it’s a party, which in some ways it is. You two are sitting in the living room, cuddling and making out while you wait for her to arrive. The bell rings and you go to answer it.

“Hello sis!” you say with a wide grin, leaning in and giving her a nice and somewhat inappropriate hug. You press your chest against her big tits and caress her back. You sniff her neck and then break the hug. If she was creeped out by you it didn’t show because she was too confused.

“I thought there was a party? I don’t see anyone else… and you’re dressed in boxers and a tee.”

You look down at your clothes and laugh genially. Both you and your girlfriend didn’t dress up because… well, there’s no party. And your step-sister, bless her soul, is wearing a tight, strapless LBD. You can see her delicious cleavage and those thighs you’ve always wanted wrapped around your face.

“Why don’t you come on in?” Rachel says, taking Amy by the hand.

“What’s going on?” Amy asks as she’s made to sit down on the sofa. You and your girlfriend are standing in front of her. You’re getting a nice peek down her dress.

“Here’s the thing,” Rachel begins. “I have a fantasy. I want to see my man fuck another woman in front of my eyes. I’ve spoken to you about this. There’s just something about being seeing his dick in another pussy while I watch from the sidelines that turns me on. And I spoke to him about this yesterday… and we decided that we’d love it if you could fuck him while I watched.”

You weren’t expecting your girlfriend to blurt it all out at once, but it was probably for the best. Your step-sister looks nonplussed. She turns to you.

“And you want this?” she asks nervously.

“Of course I do,” you reply, caressing her hair.

“Alright, then,” she says with a nervous gulp.

“What the fuck, it was that easy?” Rachel gasps.

“The truth is,” your step-sister says, standing up in front of you, “I’ve always thought you were really hot,Ross. I saw you a couple of times in the shower and it made me really wet, imagining your hard body on top of mine.”

“Well, look who turned out to be a real slut,” you say as you pull Amy in for a kiss. This time you move your hands immediately to her curvy and high ass. You knead it and massage it through the soft fabric of her dress. Her hands are on your pecs.

“That is so fucking hot,” you hear Rachel say. You break the kiss, licking the strand of saliva. You push your step-sister down on the sofa and pull out your erect cock.

“Big, isn’t it?” your girlfriend says as she sits down next to your step-sister.

“Huge. Bigger than my boyfriend’s.”

Amy wastes no time in popping your dick in her mouth and sucking on it. You grab her hair and give little thrusts in and out of her warm, wet mouth. Her soft lips feel amazing moving up and down your shaft. She has one hand playing with your balls and the other on your ass. She’s good at this.

You look at Rachel and see she has her hands down her panties, masturbating.

When you feel ready to go, you pull your step-sister off the sofa and sit down in her place. She pulls her panties down and pushes them in your girlfriend’s mouth, which you think is the hottest thing ever. She sits on your lap, and uses her hand to guide your cock inside her pussy. You both moan as your hard, erect dick stretches her warm, wet, tight pussy. You’re balls-deep inside her, and you love how it feels. You love her ass on your balls. You love her hands on your shoulders.

Amy slowly starts rolling her hips with you inside her. It’s divine. You pull her dress down to reveal her strapless front-clasp bra. You hungrily tear it apart and throw it aside, and out pop her big fat tits. Both the girls look at you with pure lust in their eyes. You lean forward and bury your face in Amy’s tits — sucking, licking, spitting, and biting. She starts riding you harder and faster. You give her ass a few nice hard spanks because she’s such a naughty girl. She loves it. And so does your girlfriend, who’s cumming right next to you.

After a few minutes, you notice your step-sister is also on the cusp of orgasm. You stick a finger in her butt, shocking her and also precipitating her orgasm. She moans loudly as her pussy tightens like a vice around your cock, gushing with juices. You’re getting pretty close too.

“In or out?” you ask breathlessly.

“In,” she moans, and you unload rope after rope of white hot cum deep inside her womb. Once you’re done, you leave your dick inside her. You both smile at each other.

“Why don’t we get your girlfriend to suck your cum out of me,” Amy asks with a smirk.

You’re not sure how to respond. You turn to Rachel, who smiles and gets up to do the job. You feel her warm hands pulling your dick out of your step-sister’s cunt. And then you hear sounds of her hungrily sucking your cum out of your step-sister’s pussy. It’s too fucking hot. And Amy is right on top of you, her face contorting in the most erotic ways as she says, “Yeah, get in there — suck it right out!”

When Rachel is done, Amy gets off your lap and lies down next to you. Rachel opens her mouth wide to show both of you all the cum before swallowing it. She then leaves to clean up while the two of you lie down to rest.

“That was fucking amazing,” you say.

“It really was,” your step-sister says, “and so freaky. It was like your girlfriend was our little bitch. Like the two of us made her a cuckquean.”

That makes you wonder. Does Rachel want to be a cuckquean? Does she want you to fuck other women and humiliate her? Tell her she sucks and will never be good enough for your dick? Is that what she wants?

Or was this just a one-time sexual fantasy? While you’re pondering this, Rachel walks back in the room with the widest grin on her face. You need to make a decision now.