Chapter 4: The assfucking
The heat between them was a slick, living thing. Adam moved with a rhythm he didn’t know he possessed, a deep, pounding cadence that came from a place beyond thought. Each thrust was a shock, a violation so profound it curled his toes and scraped sound from his throat. Helena’s back was a taut arc beneath him, her skin glowing with a sheen of sweat in the lamplight. Her face was buried in the duvet, but her sounds were clear—gut-deep moans that hitched and broke with every drive.
“Fuck, Adam,” she gasped, the words muffled by fabric. “Right there. Don’t stop. Fuck my ass. Fuck it hard.”
He couldn’t have stopped if the roof fell in. His hands, which had felt so clumsy before, were now locked on her hips, guiding her back onto him with a possessiveness that terrified him. This was his sister. This tight, clenching heat was her ass. The knowledge was a looped fire in his brain, feeding the frenzy in his body. He was lost in the feel of it, the blunt, perfect friction, the animal truth of their connection.
Her first climax came without warning. She stiffened, a sharp cry tearing from her throat as her body clamped around him in rhythmic pulses. He felt it, a series of intense, internal flutters that milked him, dragging a ragged groan from his own chest. He kept moving, slower now, riding out the waves of her pleasure until she slumped, breathing hard.
“Jesus,” she panted, turning her head to the side. Her cheek was flushed, her eyes glazed. “Okay. Switch.”
She guided him onto his back, the movement fluid and practiced. Before he could process it, she was straddling him, facing away, lowering herself onto him again. This angle was deeper. He could see everything—the place where they joined, the slight stretch, the evidence of their coupling glistening on her skin. She began to move, a slow, grinding roll of her hips that leveraged her weight against him. Her hands braced on his thighs for balance.
“God, you’re good at this,” she breathed, looking back over her shoulder. Her smile was lazy, depraved. “Such a good little brother. Fucking your big sister’s ass.”
The words were a lightning strike. They shouldn’t have aroused him further, but they did. They made it real, gave the animal act a name. He reached up, his hands finding the swell of her breasts, thumbing her hard nipples. She gasped, her rhythm faltering for a second before resuming with more force.
“You like that?” he managed, his voice a foreign, rough thing.
“Mmm. I like you inside me,” she said, her tone conversational, even as her breath hitched. “I like that it’s you. My shy little brother. All that pent-up shit finally coming out.” She ground down hard, making him see stars. “You gonna come inside me? In your sister’s ass?”
The question was a command. A second, stronger orgasm was building in her; he could feel the tension coiling in her muscles, hear the change in her breathing. Her movements became more frantic, less controlled.
“Say it,” she demanded, her voice tightening. “Say you’re gonna come.”
“I’m gonna come,” he choked out, the admission shredding the last veneer of pretense. “I’m gonna come in your ass, Helena.”
Her name, in that context, did it. She cried out, a raw, unfiltered sound as her body clenched around him again, this climax longer, more violent. The sensation of her pulsing around him, the utter filth of their shared act, the smell of sex and sweat—it was too much.
His own control snapped. With a final, desperate thrust up into her, he came. It felt like his spine was melting, a white-hot rush that blurred his vision and emptied him of every thought, every fear, every ounce of himself. He spilled into her, deep and unreserved, his body shaking with the force of it.
For a long moment, there was only the sound of their ragged breathing. She collapsed backward onto his chest, her weight warm and solid. He lay there, utterly spent, his arms coming around her instinctively. He was still inside her. The intimacy of that, in the aftermath, was somehow more shocking than the act itself.
Slowly, carefully, she lifted herself off him. The separation felt physical, a loss. She padded, naked and unselfconscious, to the bathroom down the hall. He heard the sink run. He lay on the bed, staring at the ceiling, feeling the cooling sweat on his skin, the faint ache in his muscles, the brutal, humming clarity of what they had just done.
She returned with a warm, damp washcloth. Without a word, she began to clean him, her touch matter-of-fact. Then she attended to herself. The domesticity of it was surreal.
She dropped the cloth into a hamper and crawled back onto the bed, lying beside him on her side, propped up on an elbow. Her eyes traced his face. “Well,” she said, a small, tired smile on her lips. “That was something.”
He could only nod. His mind was a jumble of sensations and half-formed thoughts. The phantom feeling of her around him lingered. The room still smelled of them.
“You okay?” she asked, her voice softer now.
“I don’t know,” he answered honestly. His throat was tight. “That was… a lot.”
“It usually is.” She reached out and brushed a strand of hair from his forehead. “You were great. Really.” She said it like she was complimenting his performance in a school play.
The casual praise twisted something inside him. He had just done the most forbidden thing imaginable, and she was telling him he was good at it. A part of him swelled with a dark, proud pleasure. The other part recoiled.
“Is that… all it is?” he whispered, turning to look at her. “Just a physical thing?”
Helena considered this, her head tilting. “Isn’t that enough? It feels good. We’re not hurting anyone.” She shrugged a bare shoulder. “It’s just us, in this room. All night, if you can keep going."
“But… after. Tomorrow.” He swallowed. “What happens then?”
She sighed, a gentle exhale. “We go get bagels. We watch TV. We live our lives.” She traced a finger down his chest. “This doesn’t have to be a big, dark secret that eats you alive, Adam. It can just be a thing we do sometimes. Because we want to.”
The simplicity of her worldview was staggering. For her, it seemed, the boundary had been crossed and now it was just territory. For him, he was still standing on the crumbling edge, looking into the abyss.
“Do you…” He hesitated. “Do you think about Mom?”
She didn’t flinch. “Sometimes. Not in a ‘let’s make it happen’ way. More like… a curiosity. She’s an attractive woman. It’s a natural thought to have.” She said it as if discussing the weather. “Do you?”
He thought of the video, the mother and son. The flicker of heat it had sparked amidst the shame. “A little,” he admitted, the confession leaving him exposed.
“See?” She smiled, not unkindly. “It’s normal. It’s just… most people never get to explore it. We’re exploring.”
Exploring. The word made it sound like an adventure, a hobby. Not a sin that could shatter their family.
“I’m scared,” he said, the words small in the quiet room.
“I know.” Her hand stilled on his chest. “It’s okay to be scared. But nothing has to change unless we let it.” She leaned down and kissed him. It was a sisterly kiss at first, but then opened up, her tongue playing with his.
The earlier exhaustion began to fade, replaced by a slow, insistent rekindling. He felt himself responding against his thigh, a thick, reluctant resurgence.
She smiled against his mouth, feeling it. “See?” she murmured, her hand drifting down. Her fingers wrapped around him, stroking slowly. “Told you. All night. I'm not done with that wonderful little cock just yet.”
His breath caught. The sensation was somehow more intense now, hypersensitive and raw. She watched his face, her dark eyes studying every twitch and flicker of surprise. “Just let it happen,” she whispered, shifting her body over his.
She guided him inside her, not her ass this time, but her cunt. It was wetter, hotter, a different kind of embrace. She sank down onto him with a low, satisfied sigh, her head falling back. The lamplight caught the line of her throat.
“Look at me,” she said, her voice husky.
He forced his eyes open. She began to move, a slow, deep rocking that made his toes curl. He gripped her hips, feeling the sweat-slick skin, the solid muscle beneath. This was different. Face to face. He could see every micro-expression, every shudder that passed through her.
She leaned down, sealing her mouth over his again. Their tongues tangled, messy and desperate. He could taste herself on her lips, a faint, briny tang that sent a jolt through him. One of his hands came up to cup her breast, his thumb rubbing over the nipple. She made a sound into his mouth, a hungry little moan.
“Suck it,” she breathed, breaking the kiss. “Come on.”
He did, drawing the peak into his mouth, laving it with his tongue. She gasped, her rhythm becoming less controlled, more urgent. Her fingers threaded through his hair, holding him there. “Good,” she panted. “Such a good baby brother. Fucking me so well.”
The words were a drug. Each praise, each explicit confirmation of their relationship, coiled tight in his gut. He thrust up into her, meeting her downward strokes, their bodies finding a synchronized cadence. The headboard tapped a soft, persistent rhythm against the wall.
“Wait,” she gasped, leaning over to fumble in the nightstand drawer.
She came back with two vibrators, one a slender wand, the other a smaller, egg-shaped device. She clicked the wand on, a low hum filling the room, and pressed it against herself where they were joined. The effect was immediate. Her whole body seized, a sharp cry tearing from her throat.
Her internal muscles clamped around him in a swift, pulsing rhythm. “Oh god, Adam, don’t stop,” she begged, her voice cracking. She came like that, writhing atop him, her face a mask of pure, unraveled pleasure.
As she trembled through it, she managed to switch on the smaller vibrator. She slipped it between their bodies, pressed against her clit. The dual sensation made her moan, long and loud. She began moving again, fueled by the relentless buzz, chasing the next peak.
He was lost in her, in the sight and sound and feel of her coming apart. His own need was a tight, building pressure in his core. She wrapped her legs around his waist, locking him deep inside.
“That’s it,” she coaxed, her eyes glazed, voice ragged. “Give it to me. Come inside your sister. I want to feel it.”
Her words were the final trigger. With a broken sound, he obeyed. His release crashed through him, a hot, pouring rush that left him shuddering and empty. She rode him through it, milking every last pulse, her own body convulsing in a final, shuddering climax that seemed to go on forever.
Finally, she stilled, collapsing onto his chest. Their hearts hammered a frantic, overlapping rhythm. The vibrators, forgotten on the sheets, buzzed pointlessly against the rumpled duvet until she reached back with a limp hand and switched them off.
The sudden silence was profound, broken only by their labored breathing. The room smelled intensely of sex, salt, and spent candles. He stared at the ceiling, feeling the slow, inevitable seep of reality back into the room.
She stirred first, rolling off him onto her side. She traced a random pattern on his chest with her fingertip. “Bagels tomorrow,” she said, her voice sleep-thick and hoarse. “I know a place.”
He turned his head to look at her. Her hair was a dark wreck against the pillow, her mascara smudged. She looked utterly content. A deep, hollow ache bloomed in his chest, something separate from the physical satiation.
“Helena,” he started, but no other words came.
“Shhh.” She pressed a finger to his lips. Her smile was soft, knowing. “It’s just a thing, Adam. Let it be a thing.”
She reached over and clicked off the lamp, plunging them into a darkness that felt absolute. In the black, the world outside the bedroom door—their childhood, their parents, every normal rule—seemed to rush back in, waiting. He listened to her breathing even out beside him, and wondered if the secret would feel lighter or heavier in the morning light.