First, disgust. But then...

James gaped at his step-sister, a post-orgasmic haze still clouding his mind, one hand wrapped around his throbbing cock as a few more drops of cum dribbled from its tip, the other grabbing one of his tits, soft flesh bulging out between James fingers.

"Ew, oh god, ew, fuck," Lily squeaked, wiping cum from her face with both hands while she turned around, flinging it on the floor. "What's wrong with you?! How could you... god... ugh!"

Her brother, meanwhile, had trouble dealing with the fact he'd just given Lily a facial. Of course, James had often fantasized about giving a woman a protein mask, but they had always been consenting partners, and certainly not his own step-sister! Whose movements had... slowed. Become less frenzied. Was she actually... sucking on her fingers?! James couldn't believe his eyes: Where Lily had desperately tried to clean herself as much as possible, his step-sister had now dropped down to all fours, wiping up drop after drop of cum from the floor, humming and cooing whenever she sucked her fingers clean of the salty, sticky fluid.

But Lily's new-found appreciation for his cum wasn't the only thing that kept James rock hard, his cock and knot pulsing with his heart beat. A heavenly scent reached his nose, traveling from his nostrils right into the deepes parts of his brain where it triggered something primal. Something that would not, could not be denied. Sniffing the air, James got up, pulling his shirt over his head and threw it on the floor. Now fully naked, James' pert sextuplet of tits jiggled and his massive shaft bobbed with his every step as he followed the scent, eyes closed to focus on his sense of smell. It became stronger and stronger; James kneeled down, inexorably drawn to its source, bending forwards and... pressed his face into Lily's hotpants-clad crotch from behind her, taking a deep whiff of the scent of her pussy as he opened his eyes to the sight of Lily's tight bubble butt.

"Ah!" his step-sister squealed, wiggling her hips against his face. "Dooon't, I'm... god, this is so wrong... I'm so wet, but we can't! You're my... mmmh, brother!"

James barely heard her. However thin the fabric covering Lily's crotch was, it still barred his access to the source of the heavenly scent that was drawing him in, so he grabbed Lily's hips and yanked her hotpants down to her knees. The smell of her pussy hit James' nose like a freight train, making his cock lurch and slap against his abs, a spurt of pre spattering over his step-sister's legs. Lily made a halfhearted attempt to crawl away, but the pants restricted her movement and gave James ample opportunity to dive forwards and bury his tongue in her folds, James' hands grabbing her hips tightly.

"Nnaaaah, god!" Lily moaned, pushing her butt back into her step-brother's face. "How is this... fuck, so deep!"

Instead of an answer, James **** his tongue inside his sister's madly twitching, dripping cunt, her scent driving him wild as he wriggled and lapped his tongue over her folds, Lily rewarding his instinct-driven tongue fucking with incoherent babbling and moaning. The taste of her juices rolling over his tongue made James' cock tremble and lurch, precum beginning to drool out and onto the floor. But he had not yet had his fill of the tasty nectar spilling over his chin, pulling and pushing his tongue inside of Lily, spurts of feminine cum splashing onto his face as Lily writhed uncontrollably under his ****. Her breaths came in short gasps, pussy squeezing down on James' relentless tongue.

"A-a-aaAOOOH FUCK," Lily squealed, her whole body shaking as she collapsed forwards onto the floor, and James tongue slid out of her with a lewd slurping sound. It definitely felt a fair bit longer than before as he pulled it inside his mouth, savoring his mate's taste, but James was preoccupied by other matters - namely the almost painfully hard, red erection between his legs. And Lily's puffy, swollen sex looked oh so inviting. James pulled his step-sister's pants off completely, spread her legs to kneel between them and pulled the barely sensate blonde's hips upwards, lining up his pointy tip with her pussy.

As James began pushing his enormous, straining rod forwards, a lust-filled groan rose from his parted lips which mingled with Lily's drawn-out moan, wet, silky hotness enveloping James' member. Once he hilted out, his knot pressing into his step-sister's labia, James just held her hips tight, reveling in the way Lily's creases squeezed and milked his cock. Lily herself gasped and jerked her hips, fucking herself on her brother's cock.

"Fuck, it's... huge, how does... oh gaawwd..." she babbled, fingers clawing at the floor.

James only grunted in response, barely able to form a conscious thought - Lily's pussy was the first to ever caress his dick, and the exquisite sensations were overwhelming his mind. Only the fact that he'd jerked off literally minutes ago prevented him from pumping his sister full of spunk. As it was, he could begin pumping into her, unable and unwilling to stop his hips from moving. The slick folds of Lily's sweltering tunnel caressed his engorged dog dick in all the right places, precum drooling into his step-sister's depths with every slap of his heavy, cum-laden balls against her body.

With every one of James' quick, determined strokes, his knot struck Lily's cunt, eliciting short, breathless gasps from his step-sister, and she soon began moving in time with James' thrusts, slamming herself back into his crotch. James' multitude of tits jiggled with every jab into Lily's nethers, the wild motion increasing his lust ever more. Bit by bit, he felt his sister's entrance give, his knot sliding in deeper with every thrust - but James seemed unable to **** it in fully, barely a third of the bulbous knot glistening wet from Lily's juices when the dilation seemed to slow.

James' humping grew increasingly ****. He had to **** his entire cock inside of his mate, knot and all, until only his sheath remained outside her. But it just... wouldn't... fit! Gritting his teeth, James began pulling his squealing sister's hips back forcefully, intent on finally filling her completely, and with every pull, it seemed easier to manhandle her. Staring down at where their bodies joined, he could see his thick rod slide in and out of Lily, her quivering lips clinging to his length, sucking him back in at the end of every backwards stroke. The bulging, throbbing knot, however, seemed to forever remain just outside her sweltering snatch.

But from the corner of his eyes, James saw the solution for his problem come into being - with every passing second, with every thrust, his arms rippled and bulged, his modest muscles quickly approaching the size of the surfers from the beach. But James barely cared how they looked; much more important was the fact that they gave him the strength to slam Lily back into his crotch with even more **** until finally, accompanied by a wailing moan from his mate, the knot slipped inside her.

"Oh god, oh god, oh gaawwdd," Lily stammered, throwing her head from side to side. She'd raised her body sometime when James had been pummeling her snatch and was now supporting herself on her elbows, hands forming tight fists. "It's so huge, too big, you're stretching me ooouuuut!"

Her brother didn't care. He had finally managed to fit every inch of his animalistic member inside her, the pointy tip poking into her cervix, the shape helping to **** it open until James was able reach her deepest parts. Lily's entrance was clamping down tightly on his shaft, just behind the knot, and James realized that this prevented any proper thrusting. But again, he found himself unable to care - the short, quick jabs he managed felt more than amazing as it was, a sentiment clearly shared by his sister, judging by how she howled and squealed under his ****.

"Yes, yes! Fuck me! Harder!" Lily moaned loudly, wiggling her hips sideways on James' dick. The additional sideways forces were enough to make her brother moan himself, James' voice sounding strange to his ears. But the feeling of his balls beginning to churn and bloat with seed was enough to wash away all his concerns, and James redoubled his efforts, pounding away at his sister's twitching and clenching pussy. His limited movements served to delay James' climax, but he felt it nearing inexorably, knot swelling even more in preparation to lock him together with his mate.

"Oh fuck, bigg... -er, I can't... take it, you're making me... nhaaAAA YES!" Lily's screams suddenly hit a crescendo, her pussy clamping down hard, forming a tight seal around James' whole length. As his sister collapsed forwards, she pulled James down with her, and the dog morph came to lie on her back, his stiff nipples pressing into the toned muscles, sliding back and forth with every thrust. Grabbing her shoulders to support himself, James lightly bit down on her neck, sucking and licking Lily's hot flesh, causing her exultant moans to become even more intense.

Wordless screams and howls of bliss were all Lily was able to make, but James wasn't faring much better - all this stimulation quickly overwhelmed any resistance he had and he felt his swollen nuts spasm and finally contract. With a guttural growl muffled by Lily's neck, James exploded deep within her, his jizz shooting in a mighty jet right into his step-sister's womb from his tapered tip. With every sticky rope of seed blasting into Lily, his hips jerked and twitched involuntarily, James' balls pulled tight against his crotch as they emptied themselves of their thick contents.

After what felt like hours of cumming, James' climax finally subsided and he let go of his sister's neck, faint bite marks remaining in her tanned flesh. Groaning tiredly, he slid off of Lily's back, coming to lie on his side next to her, still connected to her in the most primal of ways, James' knot preventing any cum from leaking out. His step-sister mumbled and murmured in satisfaction, rolling herself on her side until she could snuggle back into her brother, making him hiss in pleasure as she pressed into his sensitive multitude of breasts.

Still in a daze from the incredible experience, James wrapped one of his newly muscular arms around her and pulled her closer, Lily entwining her finger's with his and taking a deep, contented breath.