I smile at her from across the table. My stepsister Liz, who is completely unaware of my intentions, has no idea what’s in store for her. I’ve been waiting for an opportunity and now that our parents are out of town I finally have the chance I’ve been waiting for.

I feed our family dog, Duke, who is a two year old male Pyrenean Mastiff. After I’m done I walk down the hall toward the main bathroom, hearing Liz in the shower. I smile to myself and continue down the hall to get everything ready. I enter her bedroom and secure two ropes to her bed frame, one on each of the end posts by the foot of her bed. I tie secure knots leaving a loop on each rope end just big enough to fit around her ankles. Then I tie loop ends on a shorter piece of rope and leave that under the blankets on her bed. I hear the water shut off in the bathroom, and take my place behind the door of her bedroom.

A few minutes pass before she walks through the door, using her foot to kick it closed as she passes. I smile, knowing that she never looks behind her as she does this. She reaches her bed and pauses, noticing the ropes secured to the posts at the foot of her bed. By the time she looks around, it’s much too late. I’m already on her, one hand clamped firmly over her neck and the other pulling the towel away from her body. She tries to scream, but the sound never leaves her throat. She is able to breathe, but I’m holding her neck with enough force that she cannot make any sound.

I manage to force her to the bed, kicking and fighting, clawing at my arms. I squeeze her neck tighter and growl in her ear, “knock it off. Or else.” This makes her stop struggling as much, and I can feel hot tears running down her face and over my hand. I smile. This is already better than I thought it would be.

I feel myself getting hard as I slam her down onto the bed and hold her down while I secure her ankles in the loops at the end of the bed, tightening them until the rope digs into her skin. I look at her face and tell her to stay quiet, and that I was going to release her neck. She nods and chokes as I release my grip on her throat, sobs shaking her whole body. I grab a fistful of her hair and pull her head to make her face me. “ You’re going to be a good girl, right?” I ask, tightening my grip on her hair. “You’ll do as I say?” She sobs and fresh tears stream down her face. “Yes!” She chokes again, her sobbing making it harder for her to breathe.

I smile. “Good girl.” I praise her. She continues to sob as I remove the rope from under the blankets and wrap her arms around her front, securing her wrists together behind her back (like a straightjacket, without the jacket) I push her forward until she is leaning over the edge of the bed. Then I walk around to the end of the bed and unzip my pants, my 6 inch erection nearly slapping her in the face. I smear a drop of precum across her cheek and down over her lips, mixing it with her tears.

I grip her hair in my hand tightly and force her head down. Her jaw is locked, and she refuses to open her teeth. I reach down and pinch one of her nipples, twisting it cruelly. The second she opens her mouth I force my dick into it. “Don’t even think about biting me, you little bitch” I warn her. I start pumping in and out of her warm, hot mouth and groan, pushing her head farther onto my dick. I thrust against the back of her throat and she gags, starting to sob harder. The next time she gags I force myself into her throat, groaning as she chokes around me. The look on her face is priceless.

Duke suddenly wanders into the room and I smile, looking between Duke and Liz. She looks over at him and tries to shake her head, her eyes widening even more. I pat her ass and Duke jumps up onto the bed, his weight pushing the mattress down slightly. I pull Liz by her hair and force her to lay over the edge of the bed, choking on my dick while her ass is exposed in the air over the bed. I groan, her sobs shaking her body and making her throat slick with tears.

Duke presses his snout into Liz’s cunt and her whole body stiffens. She tries to lean forward, away from Duke, but my dick down her throat stops her from being able to move any farther forward. Duke starts to lick her pussy, his long rough tongue dragging forcefully from her clit up to her ass. He continues this cycle over and over again, pressing his tongue harder with each lick. I smile at the expression on Liz’s face. She is still sobbing, but the cries are quieter now and she isn’t fighting as much anymore. Her spirit is broken. I smile, having dreamed about this moment for months. She’s given up and accepted it. I’m going to have my way with her, and there’s not a single thing she can do to stop me. And she knows it.

Having the dog in on this is a bonus. I glance at Duke, and smile wider as his dick starts to protrude from its furry sheath. Not long now until the real fun begins. I pull my dick out of Liz’s throat and tell her to spit on it. She ignores me. I slap her hard across the face, leaving a red hand print over her cheek, I tell her again, an angry tone entering my voice. “Spit on it. NOW.” She begins sobbing harder again and makes an honest effort to spit over my dick. I bring it closer to her lips and she dribbles some saliva over my head, sobbing hard now.

I call Duke and he eagerly jumps down, waiting for a command from me. I lay on the bed and pick Liz up, angling my dick at the pucker of her ass. She cries loudly and I clamp my hand down over her throat again, cutting off the sound instantly. I rub her spit from my dick over the tiny hole, and then slam into her. She would have screamed, had I not been holding her throat so tightly. I push her down, impaling her onto my dick. My entire 6 inches disappears within her asshole. Her sobs shake her whole body, and I groan as her body gently shakes on me. Her ass is so tight too. I make the assumption that I’m the first person to have entered her here, and this pleases me.

I position us farther up on the bed, and place a pillow under my hips to raise us off the bed a few more inches. I smile and call Duke onto the bed. He jumps up happily, wagging his tail. His dick is still slightly visible at the end of his sheath. I thrust hard into Liz’s ass and she tries to struggle, sobbing heavily. She is helpless though, with her legs secured and spread, and her arms secured in an X across her body and tied behind her back. Duke tilts his head and leans forward, licking Liz’s pussy while I fuck her ass. She shudders, though I’m not sure if it’s from pain or pleasure.

Duke licks her pussy a few more times before jumping up to mount her. He probes her inner thigh a few times, panting in her face. She shakes her head and tries to say something, but my grip on her throat is too tight. No sound escapes her lips. Duke hits his target and upon thrusting into her pussy, he buries himself to the hilt within her. Her body goes rigid, then limp. Liz has passed out. I release my grip on her throat, reaching down to squeeze her breasts instead, twirling her nipples between my fingers.

Duke thrusts madly into her, shaking the whole bed. I groan and thrust into her ass. I eagerly take advantage of Duke’s forceful thrusts, pushing her back and forth between us. I can feel something large plopping in and out of Liz’s pussy through the thin tissue between her ass and pussy. I realize quickly that it’s Duke’s knot. I groan, Duke’s growing knot stretching Liz’s pussy to its limits and making her asshole even tighter. He thrusts into her with a final audible “pop” and his knot continues to grow a little within her pussy. I groan loudly, gritting my teeth together as I pump cum into my sister’s ass at the same time as Duke unloads into her pussy.

We stay this way for a while. I groan, feeling Duke’s knot pulsing in Liz’s pussy through her ass. Finally, after what seems like a long time Duke pulls his knot out. I smile and reach around to feel the dog’s cum streaming from her pussy. I pull myself out of her tight ass and untie her ankles, then her hands. Liz is really out cold. I lay her down, tucking a stray hair behind her ear from her tear stained face. I step back to look at Duke’s and my handiwork. I smile, the view of my cum oozing from her ass is really a sight to see. I look at her pussy next, and lean closer then rub a finger through her lips. I bring my finger up for a closer look and realize that its not only covered in dog cum, but blood too.

I realize then that Liz just lost both of her virginities, her ass to me and her pussy to our dog. I smile, my dick twitching at the thought. I look down at Duke, who is panting happily, his tail lazily wagging. I take some very detailed pictures on my cellphone. Then I turn to leave and pat my leg, signaling Duke to follow. I carefully close Liz’s bedroom door behind me and walk to my own bedroom, satisfied with my deeds. I flip through the pictures, smiling. This is just the beginning.

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