Incest Seduction/Try to be a good girl
What's wrong with you? You're secretly doing it in front of your parents after secretly doing it in front of your brother but you're not afraid of getting caught, you're just... afraid. But maybe that's the problem; you aren't the one having sex right now. Despite all but outright dreaming of fucking your big brother before today, you never really wanted to be forced to fuck him, or anyone really. Even when you "fell" onto daddy's cock before you could have scrambled up onto the counter to get away... you just chose not to. You let daddy fuck you. Not that he asked, but you definitely complied. And you loved that he wanted you so badly. But this... is different.
You wanted this, right up until it happened, but Zack didn't. Having to hide his erection inside you thanks to your pestering means he isn't doing this due to some overwhelming desire, like he just couldn't help himself. You didn't give him a choice. And now you don't have a choice either. You can't change your mind, you can't be coy, there are no options. You're tied down and held in place while Zack forcibly stretches and rearranges your insides to make room for his quite colossal cock. It makes you question so many things; like whether daddy is smaller than Zack or if daddy just roughed up your cherry enough to make your brother feel monstrously large. But more importantly, is it really rape if you asked for it?
You do your best to swallow your anxiety, even though you can feel yourself starting to tremble. You just don't know how to say "this isn't what I wanted" after literally begging for it incessantly. But it's especially hard to think through and process all of this when your sibling's panic-inducing cock is also the source of the achy pleasure emanating from your recently-virgin sex; the same pleasure that has convinced you to gradually accept and explore this crazy morning's events.
Besides, you already reasoned your way through all this. You're a slut now, remember? It doesn't matter if being tied down freaks you out. It's your own fault. Mommy makes the rules and she decided you needed to be bound naked in the middle of the kitchen so you can't defend yourself. So what if the idea of rape is better than the experience? You deserve it after pushing your reluctant brother so far. And even if he's only fucking you in anger, at least he's fucking you. That achy, blissful, tingly feeling that daddy filled you with so recently is still here, you just need to focus harder to find it.
You want to be a good girl. A good slut. It's the least you can do for your brother. You just need to breath for a minute.
"S-slo..." you eek out. That's the wrong word to be sure, not that it was intelligible, but you don't know exactly what you need right now. This is only (technically) your second time.
Your brother's expression softens for a moment. He looks you over with the familial love you're used to seeing from him. But that doesn't last long. He instead looks down then quickens his pace which also makes his thrusting more obvious.
"Yeah, shut up. I know what you want."
His flat nearly soulless reaction is discouraging, and yet his increase in tempo brings with it shallower and more pleasant movements. You swear he's still buried to the hilt, but at least you no longer feel him in your ribcage.
With your brother unwilling to look you in the eye, you tilt your head back and look up at the unremarkable kitchen ceiling. That lack of visual stimulation swiftly amplifies the physical sensations accosting your body; The silky bindings around your wrists; The discomfort in your shoulders; The stiff arch in your back; Your stretched out form is extra sensitive to everything around you, and that's on top of being naked and horny. Your now concave stomach collapses even further with each breath, apparently not satisfied with how stretched you already are. That, in part, may be what is putting extra pressure on your insides and is causing your brother's penetrating rod to feel more like a baseball bat than a penis.
Your brother hooks his hands on the inside of your thighs and pushes down on you, spreading and then flattening your legs against the table. If there was any pretense left it was surely gone now, not even a finger on your chest and your feet bobbing about in rhythm with Zack's thrusts. Having your legs forced apart also opens up your crotch, your pussy somehow feeling wider, although Zack also drops deeper. Any of it hardly matters since you're already stretched to the limit in every direction by your sibling's shaft, but it is a little different. You start to think about how other positions might feel. You only know of a couple, but "reverse cowgirl" sounded fun.
Eventually your eyes close and you start to accept your lack of control in all of this, wanting to lose yourself in the experience. Daddy was so much gentler with you than Zack. It's true that Zack is trying to punish you but you'd be lying if you said they didn't both feel great inside of you, even with how uncomfortable your brother's cock is rammed so deep inside you.
"Are you coming baby?"
Mom's voice rudely snaps you out of your trance. But when you look around you don't see her; daddy either. You have to crane your neck and twist your head before you spot them, and you're just barely able to with your bound hands and arms impeding your view of the dining room. You find them just on the edge of your vision sitting at the table; mom, dad, and... your sister Dawn. Embarrassment hits you again as you realize that every member of your family has now seen you writhing around on display with a dick buried inside you. You have no idea what mom might have told her by now, but you find it hard to believe she wouldn't have freaked if she knew you and Zack were fucking.
"Uhh, not... yet," croaks your brother.
"You should. You should come baby. Come and sit next to mommy. Breakfast is waiting."
Mom's soothing and especially sultry voice brings your brother to buck into you a little harder. A moment later and he's struggling to hold back a groan when his movement all but stops. Although his expression doesn't change it is at least obvious to you what he's doing. Zack's rod twitches inside you, throbbing and pulsing in distinct bursts. A few seconds of silence is followed by a drained exhalation from your eldest sibling. A few more seconds and he calmly steps away, his meaty cock finally unsheathing itself from your tender little pussy. You openly moan as he pulls out, his girthy length pulling past your labia inch by inch, your tight lips eager to retain the juices coating his shaft. When the tip pops free you gasp, your limbs stiffening. It was so hard to deal with so much dick all at once but as the pressure and anxiety subsides you just melt, your arousal washing over you with an intoxicating effect.
His body no longer pushing against you and his hands releasing your thighs, your legs slip past the edge of the counter. Your butt nearly follows your legs, teetering on the edge, but your taut bindings and already stretched body keep you from slipping any further. There is one more thing that makes it past the edge however; your brother's semen. You shiver as a hefty glob of his seed rushes out of you. From the loud smack it makes against the floor you can only imagine it is the same size as his fist.
Sore and tingling. Tender and electrified. Your body is a mess of sensations. Your lower lip trembles along with your clit. Now that you can fully experience your senses again, you suddenly feel empty. Ever since you jumped on daddy's dick actually. You had no idea how much you needed it, how much you were missing out until that moment. And now, even after being impaled on your brother's sturdy shaft, you're still not satisfied. This is cruel. It's not fair. It's practically maddening.
You're still leaking onto the floor, legs dangling, when Zack tosses your robe next to you. He doesn't stop to say sorry, or even 'thanks', on his way past you to the dining room. He doesn't even look at you. He just mutters "Happy?" and keeps walking. At least he brought you your robe. And though that makes your heart flutter at first, when you take a closer look you see a wet shimmering smear across the front of the kimono. Zack used your robe to dry off his cock!
Daddy greets your brother when he takes his place at the table. You've never been more conflicted and confused. Here you are, naked, bound, and freshly fucked in plain sight of your entire family, and not one of them is the slightest bit inclined to untie you so you can join them for breakfast? Don't you matter? Although you can feel the shame bleeding from your ears you equally want one of them, any of them, (all of them?) to come finish you off and bring your morning of abject depravity to an explosive end.