“So like – how can you even think about – being able to-”

“I’ve been practicing.”

“On what?” Max grimaced and squirmed a little bit, paws gripping his sister’s shoulders, trying his best to keep most of her weight off of him. As soon as she had suggested this, he knew that it was going to be a hell of a time figuring out the right angle, but – the feral dog above them seemed to have no such worries, the beast’s tongue lolling out, his hot breath puffing out across both of them, and most importantly, his full, hefty shaft hanging down near where Max thrust up into her, radiating its familiar slick, wet heat. “Those big fuckoff balls outside the Target?”

“If I told you,” Erika replied, and lifted up a little bit, “then you’d wanna know where I keep it so you can try it out yourself.” Her plump sex squished and squelched around where her brother had buried himself to the knot inside of her, and he could feel the way she reached down to spread herself around him. “Also, those are called bollards.”

“Isn’t that what the British say when they’re pissed?”

“That’s bollocks. Now – fucking – hold still so I can… make sure he’s…”

The banter was one thing, but admittedly Max just could not get enough of lifting up into Erika like this, feeling the silken wetness of her arousal sleeve so snug around him, having her scent in his nose and her warmth against his body – while at the same time receiving the quick, rhythmic sprays of feral canine pre out across him from where the good boy stood. Rich, glistening pinkish-white meat, strung through with dense spiderwebs of veins; hanging almost straight down underneath its own weight, balls lifting with each throb, shaft itself bouncing forward with those sprays.

One paw still on her shoulder – she had lowered herself down onto him from above, then lay back and tugged the dog forward – he reached down with the other, ran his fingers across her bare breast, her chest, her belly, brushing over the little pinpoint nubs of her other nipples, following them in line. Down there her fur had become matted with the constant squirts of the dog’s excitement, the salty, musty sprays soaking through, dribbling down her body, now smearing across Max’s fingerpads as well. It was hard to tell what of the wetness dripping down his sheath and pooling along his sack was hers, and which was the dog’s.

“Move.” She lightly slapped his paw away, so Max shifted it down to her thigh instead. Talk about soaked… he thought, unable to keep himself from gripping there, tugging down and out of her, sinking right back in again. Can’t blame her. There’s something just – so fucking hot about pulling out, being all wet with her, then getting sprayed by this dog, and sliding back in… “I’m gonna – lift up a bit. Hold still.”

“Yeah, I-” But then she did so, and it took every bit of Max’s willpower to resist lifting up to follow her. Thick, full lips slurped across the contours of his shaft, walls of succulent wet meat inside tugging slightly outwards despite the coating of silken slickness. He closed his eyes, shivered again, lay back…

...and perked his large, radar-dish ears towards the distinct jingle of the feral dog’s collar upon a tug of the leash. More of that panting, more hot humid breath wafting down across both of them; Erika murmured something underneath her breath to him, “good dog, that’s a good boy, come on now,” and squirmed where she lay across her brother beneath. Max shifted both paws to her sides, holding tight, trembling with the anticipation, still twitching, throbbing, pulsing where he remained half-buried inside of her.

“And then we… just…”

Erika pushed around him, those same inner walls squishing down around his shaft. He breathed a low, shuddering moan across her shoulder, dug his fingers into her sides even more firmly, tried his very hardest to not thrust deeper, but then froze with the sudden sensation of sharp, tingling heat lining up against the underside of his shaft. Greasy slickness smeared across him, the dog’s cock squishing in against him as Erika guided him forward; soon he felt the beast’s pulse thrumming alongside his own, squishy-firm shaft shifting a little bit against his own, tapered tip nudging in, finding its mark, pushing deeper, bit by bit.

“Good boy… good boy… slow and steady, now, let me just… get you…”

Another jangle of the leash, a little catch of breath, the distinct sound of that broad, flat tongue flicking out across the feral’s chops – and then Erika suddenly shuddered atop her brother, and he felt the leash flop limp against his shoulder. Then two forepaws slid down into place near his shoulders, and when he opened his eyes again he looked straight up into the opened maw of the feral dog, and then things became much tighter where he was buried-

-and the thrusts began, fast and hard and fervent, thick coating of greasy slickness across both of them easing the movement as the feral pushed deep. Max groaned with the sensation sliding across him and resumed his own pace, quite a bit slower for his angle; Erika had propped herself up onto her elbows on top of him, and he felt the quick, unsteady breaths she had to take, her teeth gritted, her entire body trembling with the feeling.

“Are you-” Max swallowed, the lower half of his body reflexively lifting itself up into the motion. The dog’s balls bumped down against his own with each of those rapid thrusts, audibly smacking for the wetness dribbled across him – “okay-?”

Erika nodded, still lifting up, still trembling all over. “Yeah,” she panted. “Yeah, it’s – it’s just – ah – a lot, and-”

“Need more – practice?”

“No, I – mmh – need you to – fuck me harder, dipwad. I’m not gonna break.”

A feral dog fucks my sister better than I do… It was hard to focus with the beast’s shaft squeezing against his own, trying to push him out of her spade with every movement even when he lifted up and sank in deeper. His paws shifted from her sides down to her thighs, then underneath to lift her up; Max raised himself from where he lay, spreading his legs further to thrust up into her, reciprocating the dog’s eager, fervent motions, squeezing right back in against him. I’d be annoyed about that if it weren’t – so fucking hot…

It was a good thing their parents were out of the house this weekend again, too: the longer it went on, the louder and more eager Erika’s panting moans became. She threw her head to one side and then the other, paws alternating between reaching up to scruff into the dog’s fur, and then sliding beneath herself to try to yank her brother up deeper inside of her. Max received a few dribbles of hungry drool across his muzzle while trying to find a spot to breathe, and on reflex he flicked his tongue out to lap that wetness off. The sticky slickness smeared across the inside of his mouth; he shivered again, sighed, and lifted his head forward a bit, half wondering if he might be able to fish for the dog to lean in and lap directly across his lips.

“Do all dogs-” He swallowed again. “Smell like-”

“You’re a dog. Trust me, his dick smells exactly like yours.”

“No it doesn’t! He’s-”

“Maybe when I’m done with both of you – ah – you can – clean him up, and I’ll clean you up… and then…” Erika wiggled her arm over and underneath his head to lift him up against her. “...we can… make out and… exchange flavors…”

The longer she went on with that, the better of an idea it became to Max. He tightened his arms around her, once again digging his muzzle into her neck; she smelled of herself, of course, and then a little bit of the soap the siblings had started to share in an attempt to hide their deviancy from their parents, and the familiar clinging stench of her own arousal mixed with that of the feral dog still pounding down into her from above, his cock sliding across Max’s, so much hotter, so much wetter than his own. He shifted his paws up and down her body, now squeezing one of her breasts, now pushing down along her spade stretched around both of them, now coming up to feel at the dog’s slick, slimy sheath, now sliding down again.

“Can I-” He gritted his teeth. “-inside-?”

His sister clenched down around him. Above both of them the dog huffed, jerked within his rhythm, and then continued thrusting.

“You better fucking not. We had that scare after the water park – and-”

“That was-” Max pushed in deeper, able to feel his knot starting to swell out, his peak approaching. His toes curled; he thought about reaching up and yanking that dog’s muzzle down to his, to get that tongue inside his mouth; he wished he was in the middle, so that he could get his fur all soaked and matted with drool and feral pre. “-your idea! You told me – not to-”

“You still fucking did it, and-”

His paws slid down to her waist, at once gripping tight and pulling her down further. Max groaned, eyes wrenched shut, teeth gritted; his hindpaws kicked, he lifted up, shivered, bucked, trembled, jerked – and felt himself slip in and then tie inside of her, good and deep with the succulent, silky wet inner walls sleeving so snug around him. Knot came first and load second: his toes curled with the approaching sensation, his teeth gritted, his breath caught in his throat… his sister growled.

“You – little-”

For the moment Max was incapable of speech. He lay back with his hips hoisted up into the air underneath her, every muscle in his body tensing as he flexed towards his peak. The dog scrabbled for support, forepaws brushing across his shoulders, Erika’s chest, the bed underneath them, then back again, but then before long he bent in close, widened his stance, and pounded at her faster and harder, warm balls sagging down across Max’s then, suddenly, tugging upwards, closer, tighter.

Right there at the edge of his own finish, so so close, his eyes snapped open “Oh,” he rumbled, “I think he’s… about to…”

Erika squirmed. “I swear to fucking God I’m gonna do exactly the same thing that – I-”

Then words devolved into gasps, yips, groans… moans. Hot breath puffed out across Max’s face, so sharp and sudden that he had to turn his head away against the way the dog leaned, teeth clamping on Erika’s shoulder. The pressure inside of her tightened, feral knot squeezing in against his own, sensation growing as the beast pressed him even deeper; Max yelped out, his cock getting pushed further out of his sheath by the pressure at his root, the sensation more than overwhelming with the feral shoving in, finding a place just inside for his knot, forcing Max’s past – and then that pressure grew, grew again, swelled, pulsed, and sealed in place, with the first of countless loose, watery sprays of feral seed mixing with his own inside of her.

It felt like he was standing at the edge of a cliff, constantly about to tumble over, never actually doing so. Last Halloween he had accidentally tied Erika’s tailhole at a family party underneath their costumes, and the two had had to walk around while pretending they were not locked in a mutually overwhelming situation, and that had put enough of a strain on his root that he was sore for days – and this was like that but more, each of the dog’s pulses squeezing in against him, pushing him closer and closer until – finally, finally, that sensation peaked – he gasped – he jerked – he flexed and tightened, all his muscles trembling, coming together…

...and bucked, bucked again, jerked again – but felt that pressure building up down beyond his knot and root, locked in place, plumbing effectively blocked by the dog’s knot squeezing down underneath his own. And that was pleasurable torture, his orgasm ongoing but unending, the urgent pressure right at the edge of releasing but never making it there.

He tapped at Erika’s shoulder. “How long do – feral knots – last?”

“Why are you asking me? You’ve had him up your ass more than – I have. But I bet if I keep…”

Around his already strained knot, Erika’s sleek walls and lips tightened, squished, pushed out, tightened again. A trickle of slick, sweet heat dribbled down from inside.

“Erik-a-”

“God, you’re both in there… fucking deep…”

“No, just – I am. His knot is – stuck between mine and my sheath, and he’s – pushing me in deeper.”

“Yeah, I can… feel you at my tonsils from behind, dillweed. Shut up. It’s hard to breathe with him – lying down on me.”

“How long is-? I’m about to fucking die.”

“Oh, you’ll be fine. Imagine how I feel.”

“You don’t… seem…” Max reached up and patted at the dog’s haunches. The beast huffed again, wagged his tail… throbbed. “All that bothered.”

“I’ve already pushed your knot out of my pussy once. I bet I can do it again…”

She’ll just be opening the floodgates at that point, Max thought, bracing himself. As soon as he’s out, all of mine is gonna just… flow out and into her…

“Ready?”