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Dad said I couldn’t do anything with a boy I wouldn’t do with my own brother. So guess what, big brother?

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I’m going to have sex with my boyfriend.

Sorry if you think that’s too much information to give my big brother. But we’ve always been kind of open with each other.

What? No, I never promised Dad I wouldn’t have sex with him. I’m eighteen years old now. It’s bad enough he made me wait until I was this old to date.

I mean, sure. I did make a promise to him. But it wasn’t about not having sex. I promised that until I moved out of the house, I wouldn’t let a boy do anything to me that I wouldn’t do with my own brother.


Come on. Think that one over a little more.

[laugh] Bingo. Finally the light turns on. Yeah, you and me are going to have sex, thereby allowing me to have sex with my boyfriend or anyone else. It’s the loophole in the promise I made. If I bang my brother, then I can bang anyone. And in the process teach dad a lesson about trying to interfere with my love life.

[sigh] Except not a very good lesson, because obviously he can never know about it. My spite only goes so far. Even if I found a loophole so he technically couldn’t get mad at me for sleeping with my boyfriend, the whole fucking my brother part might sit poorly with him.

So, what do you say to popping your little but legal sister’s cherry, big brother?

[pause for reply]

Oh, come on. I know there’s never been any sexual tension between us. No games of doctor or you spying on me when I was changing, or showering. At least that I know of. But I have to register as a girl on your radar at some level. And a cute one at that. Let’s be honest here, too. Girls as cute as me that are still virgins are a pretty rare commodity these days. And how many guys can say that they fucked their sister?

I mean, I guess I don’t really know, because that kind of thing doesn’t really get talked about. And you really shouldn’t talk about it either after we do it. But that’s not the point. You can do me. You can have fun breaking taboos and breaking my hymen at the same time. I’ll probably have fun too, although I kind of expect my first time to be kind of a mixed bag. I’d much rather have sex with my boyfriend for the first time without the distraction of losing my virginity at the same time anyway. So again, it just makes sense to lose it to you. And it makes sense for you to take it from me.

I mean, just look at me. You had to wonder why I didn’t ditch my schoolgirl uniform as soon as I got home like I usually do. Oh, I undid a button or two on the blouse and the skirt rides a bit higher. I even tied the blouse off at the stomach. I’m a porn movie or music video waiting to happen.

And they wouldn’t allow this level of makeup at school. Not that Dad would have let me leave the house this morning with it on. It’s for your benefit, like all of this.

Or… look. I was most definitely wearing panties until I got home from school. But not now. See?

[laugh] Oh, that got your attention. I can work with that. Do you like how it looks? I shaved it. Not for you. For him. But you can enjoy the look of it too, especially if it makes you more likely to fuck it.

Just look at it. It’s just begging to be forced open by the tip of your cock, then filled completely as you sink all of the way into me. I’m sure I’ll be so very nice and tight, and hot, and wet…

You graduated last year, so you don’t have a uniform like me. But you go to college, which is school, and that makes what you wore there today your school clothes. So let’s get you out of your school clothes… and into this schoolgirl…

As I move close and help you with your shirt, you can’t help but smell the perfume I put on this morning, or the shampoo in my hair. Maybe even the bubblegum I chewed on the way home. You on the other hand smell like books and old buildings, and other college stuff. It’s actually kind of nice. My boyfriend smells like body spray and energy drinks.

Now we take your pants off. It’s hard to hide now that you’re… well, hard. You got a boner for your little sister, you pervert. [laugh] Which works out pretty well, considering what we’re going to do.

I thought you’d be smaller though. You’re bigger than the pictures he’s sent me of his cock. I thought you’d kind of be a practice dick that would get me ready for the real thing. But… you are the real thing. And the first cock I’ve seen in person.

Or the first one I’ve touched like this.

I wrap my fingers around it, admiring your cock at the same time I admire my impeccably done pink fingernails. They’re shiny and hard, but my hand is so soft, isn’t it? And it slides so gently up and down the shaft of your cock.

[giggle] This is one of the things he asked me to do for him. He’d be mad if he found out you got it first. And I guess the fucking you part wouldn’t go over well either. But he’ll never find out.

Oh, is that pre-cum? I’ve heard about it.

Can I… can I taste it? Just out of curiosity. But also, if it’s something awful tasting I should be ready for it before I have to taste his.

Thank you. All it will take is running the tip of my tongue over the tip of your cock.

[short pause]

Mmm. Not bad, actually. It doesn’t hurt that the flavor of bubblegum is still strong in my mouth.

So, big brother… are you ready to fuck me?

Mmm, yes. That’s a much more confident answer than when this all started.

I have a condom, but I really should save that for when I’m with him. That won’t be for a week or maybe a little long. I should really get onto some kind of regular birth control, even if dad would freak out if he found out about that. But I’ve done the math, and tonight I should be safe. Well, a lot safer than I will be next week. I also want to say you can’t get pregnant on your first time. But I also want to say that’s something I heard from my friends, and their advice isn’t always the best.

You’re doing me a big favor my fucking me too. [laugh] I’m doing you a pretty big favor myself. But because I feel I kind of owe you, I’m just going to save this condom. Besides, my big brother deserves to fuck me bareback. What’s the worst that can happen?

Um, don’t answer. We both know what the worst case scenario is. Suddenly my schoolgirl uniform doesn’t fit as well, and while my breasts become even more awesome, my life gets far more complicated. I do want to have a baby someday. Just not nine months from today. And not yours. No offense, but you are my brother and I don’t want to have to explain this to dad anytime. Or to our baby sometime in the future when the DNA test they splurged on comes back all weird.

Sorry, I didn’t want to spoil the mood or anything.

[laugh] Except I didn’t, did I? You’re actually harder than you were before. Does my big brother have a breeding kink?

Or do you just like the idea of knocking up your baby sister?

Either way, I can work with it. Not in the sense that I’ll actually let you impregnate me. But we can have some fun while we’re fucking.

Speaking of which… we only have so much time until dad gets home. Oh, we still have time to do it without rushing at all. But I need to clean up afterward and get back to looking like my angelic and completely virginal self afterward.

I think I’ll leave the schoolgirl uniform on. You don’t mind if I do, do you?

[laugh] No, of course you don’t.

Then I’ll just move the stuffed animals off of my bed. You can help me. Be sure to turn them facing the other way when you put them somewhere, so they can’t see what we do. They wouldn’t understand.

There we go. Now there’s more than enough room for me to lie on my back on my bed. It’s a big bed. There’s irony in dad buying me such a big bed, but not wanting anyone other than a stuffed animal to share it with me. And irony in it being his own son to be the first person to fuck me in it.

I’ll pull up my skirt, once again showing my incredibly photogenic and fuckable pussy. A pussy that for today is all yours, big brother.

You’re not just more well-endowed than my boyfriend, you’re bigger overall too. But it doesn’t bother me to have your body get on top of mine, so his shouldn’t either. Oh, I’m nervous. This is going to be my first time after all. And this is incest. That’s no small thing, even if I try to pretend it isn’t.

Oh. And there’s the very real chance you might get me pregnant.

[laugh] Oh, you liked that, huh? See, I told you I’d make this fun for you. Well, even funner than popping your little sister’s cherry might normally be.

Speaking of which… my cherry isn’t going to pop itself. I mean, I could do it myself, but that seems like a waste, what with you already on top of me. I don’t really value my virginity too much. I always saw it as kind of a burden. One that you’re going to help rid me of. But to you right now, I think it’s just something else to make the moment even better..

Oh. There’s your cock. You found my pussy easily enough. I’m actually pretty wet too somehow. I think seducing you kind of put me into a special mood. I have in mind much more foreplay when my boyfriend and I do it. I’m not sure if he’ll agree though, so I want to make sure this works without it.

That’s it. Try to get it into me. You can push harder. I won’t break. Well, maybe one part of me, but I don’t need that anymore. I had that virginity for eighteen years. You can have it now big brother.

[soft moan] It’s starting to go in. It’s happening. We’re really going to do this, aren’t we?

No, I haven’t changed my mind. But I might, so hurry up. Do it. Take my virginity big-

[moan as entered]

You did it. We… we’re doing it. Sex. Incest. All of that stuff.

So this is what it feels like to have a cock in me. Or at least, this is what it feels like to have my brother’s cock in me. I’ll be a little disappointed and embarrassed if it’s not as good when my boyfriend does it.

Oh, it was a little uncomfortable as it went in. But not too bad. And best to have you take care of that than him I think. When the time comes, I’ll be sure to make a cute little pained face and an adorable little yelp to make him think he was my first lover.

I hope he’s as patient with me as you are, too. I kind of think he’d just start pumping away as soon as he’s in. Not like you, who just waited to make sure I was okay.

But I am okay, and getting more okay. So… you can move if you want.

And you do want, because you begin moving as soon as I give you permission too. But gently, just like you first took me. Oh, you’re going to spoil me for other men if you aren’t careful, big brother.

But maybe I’ll spoil you for other girls? There won’t be too many more virgins for you. Nor too many actual schoolgirls. And no more sisters, unless dad has a secret family somewhere. Don’t get me wrong. This is turning out better than expected. But it’s obviously a one-time thing. Then I’ve kept my promise to dad, and lost my virginity under my own terms.

But would you maybe like to… well, you know… kiss me as we do it? My face is right here, right under yours. I did spend a lot of time on my lips to make them even more kissable, even if kissing wasn’t specifically on my mind. I was thinking it would be weird to kiss you like that but, well, we are fucking, so there’s that.


Mmm. That’s nice. And it frees me up to kiss my boyfriend now, too. That was my first kiss. And a pretty good one. I maybe should have done the kissing before the fucking part, but you didn’t seem to mind.

Wait. What’s that noise?

No, silly. I know what that noise is. Stop moving and it will stop too. Just hold still for a moment.

Oh my God. Dad’s home early. I can hear him in the kitchen below.

We should stop. Not just stop moving, but stop stop. He’s home. And my door isn’t even shut. This could end so poorly for both of us. Although to be fair, he’d probably blame you.

Except.. . I kind of don’t want to stop. Do you? He usually spends some time downstairs when he gets home. He checks and then reads the mail, then looks at the newspaper from the morning. He’ll probably be down there another half hour.

Or, he could come up the stairs in the next minute, and see his two children fucking each other.

Okay, we have to be careful then. We can’t be too loud. And we have to listen for him on the stairs. Except I don’t remember ever hearing anyone on the stairs in the past. And I’m surprised I heard him downstairs at all with our sounds,and the blood rushing in my ears.

[sigh] But then you’re moving in me again, and I don’t really care. It feels good. Far better than it has any right to. And knowing dad is downstairs somehow makes it better. You may have a breeding fetish, but I think I have one for danger. For being caught. Not that I want to be caught. But the danger of it makes me feel so excited.

You can move faster, as long as it doesn’t make it louder. We can’t take as long as I originally thought. But don’t rush just because dad is downstairs and he’d kill you if he walks in on us. And no offense… if you’re dead at that point I’d just blame the entire thing on you.

[moan] Me wrapping my legs around you might be hard to explain though. But I can’t help it. I want to pull you deeper into me. This was just supposed to be a weird kind of revenge sex thing against dad. And practice sex for my boyfriend. But it’s turning out to be a whole lot more.

Plus I’ll probably get pregnant with my brother’s baby.

[laugh] Oh, you didn’t think I forgot about that just because dad got home, did you? If anything, our daddy being home just made me think about you becoming a daddy yourself. Maybe I got the math wrong, and today is more dangerous than I thought. Or stuff and babies happen, despite what the math says.

What would dad think of that? His daughter and son making him a grandchild right over his head?

Oh, I know what you think. That’s turning you on. And somehow, it’s turning me on too. Suddenly, getting pregnant with my brother’s baby doesn’t seem like the worst case scenario. I could be pregnant by the time I sleep with my boyfriend, and not even need a condom then. Yet another benefit of you fucking me first.

This would still be our only time, even if you did impregnate me. It just has to be. Especially if I get pregnant, but also if I don’t. Knowing what our kinks are, it’s way too dangerous. And I do have a boyfriend. This stuff today doesn’t mean anything.

Does it?

I’m so confused. It wasn’t supposed to be like this. Not just with dad coming home early. But with me liking this so much with you. Or wanting you to make a baby in me. I’m a little scared, but also feeling so alive right now.

Fuck it. Try your best to knock me up. And fuck dad. If he walks in, just keep on going until we finish or he pulls us apart. And fuck my boyfriend. He suddenly seems far less important right now. For today, you’re my boyfriend. But you’re still, and will always be my brother.

I’m going to cum soon. I’m going to feel a lot of things physically, and then after I might feel a lot of things emotionally that I wasn’t expecting. But I don’t care. I just want to be full of your cum, and maybe your baby soon. I know it’s wrong, but that’s part of what’s making it so good for us both.

Yes, that’s it… breed me. Breed your little sister...\

[orgasm or improv to orgasm]


Oh, Hi Daddy.

[laugh] Made you look. God, that would have sucked, wouldn’t it? I think I heard him go back outside again actually. I think he ran to the store.

That gives us enough time to get cleaned up before he’s back. Then we can pretend that it never happened, and I can go forward with having sex with my boyfriend.

Except… we both know that’s not going to happen, is it?

We’ve started something we can’t stop so easily. Not until we’ve explored our feelings for each other. And each other’s bodies.

And quite possibly, until we’ve gotten me good and pregnant.

But Dad did say that I couldn’t let any boy do anything to me that I wouldn’t be comfortable doing with my own brother. Well, I’m very comfortable doing a lot of things with my brother now. And we’ve just unlocked the whole pregnancy thing. Or will soon if we haven’t already. And there are all kinds of other fun things we can unlock still.

But you unlocked the best part of me already. You know what part that is, right?

[short pause]

Oh. Well, I was going to go with my pussy. But when you said my heart… well, it’s very sweet of you to say. And honestly, it’s entirely accurate, especially after that answer. My boyfriend never would have said something that sweet.

Except he did. Because you’re my boyfriend now, big brother. And my lover, and hopefully the father of far more children than I originally planned on having.

[sigh] I love you so much, my sweet and sexy big brother. And I plan on demonstrating how much every chance I get.

[laugh] Remember how you hated how I wouldn’t leave you alone as a little girl? Something tells me you won’t mind your little sister hanging around you so much anymore…