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Jungkook had always liked the quiet of his apartment. Seventh floor, big windows overlooking the Han River, soft lighting, and enough space for him and Bam to coexist without feeling cramped. He worked from home most days—producing tracks, editing videos, answering emails—so the big Doberman was his constant shadow. Bam had been with him since he was a clumsy puppy, all legs and ears, and now at two and a half he was a solid, muscular dog with a glossy black-and-tan coat and way too much energy.
Lately though, that energy had taken on a different edge.
It started small. Bam would press up against Jungkook’s leg while he was cooking, hips twitching in short, restless thrusts. At first Jungkook laughed it off, pushing him away gently. “Yah, Bam-ah, go find a toy.” But the dog kept coming back, more insistent each day. By the end of the first week, Bam was humping anything that didn’t move—couch cushions, the edge of the bed, even Jungkook’s favorite hoodie when it was left on the floor. His cock had started slipping out more often, slick and red, the thick knot at the base already swelling even without anything to grip.
Jungkook did some quick research and realized what was happening. Bam hadn’t been neutered. The vet had suggested it when he was younger, but Jungkook had put it off, thinking it wasn’t necessary. Now that decision was staring him in the face every time he tried to sit on the couch and Bam immediately tried to climb on top of him.
One Thursday evening, after a long day and three bottles of soju shared with himself, Jungkook was sprawled on the living room floor in nothing but loose gray sweatpants. The TV was playing some drama he wasn’t really watching. Bam had been pacing for the last hour, whining low in his throat, tail stiff. When Jungkook lay down, the dog was on him in seconds.
“Fuck… Bam,” Jungkook muttered, half-laughing, half-groaning as the heavy dog mounted his thigh. Bam’s hips jerked hard, that slick cock sliding against the fabric of his pants, leaving a wet streak. The dog’s front paws scratched at his sides, claws catching on skin. Jungkook could feel the heat of him, the way Bam’s body trembled with pure instinct.
He tried to push him off once. Then twice. But the soju made everything feel warmer, slower, less shameful. Bam’s cock kept rubbing against him, urgent and animal, and Jungkook’s own dick twitched traitorously in his pants.
“Alright… okay,” he breathed, voice low and rough. He rolled onto his stomach, heart hammering. “Just… get it out of your system, yeah?”
Bam didn’t need to be told twice. The dog’s weight settled on his back immediately, strong and heavy, front legs wrapping around Jungkook’s waist. Jungkook yanked his sweatpants down just enough, face burning even through the alcohol haze. He felt the hot, slippery length of Bam’s cock sliding along his ass, searching, prodding. The dog thrust wildly a few times, missing, before the tip finally caught against his hole.
Jungkook hissed at the first push. It was blunt, wet, and way thicker than he expected. “Easy—fuck—” But Bam didn’t do easy. He drove forward with a powerful snap of his hips and the head popped inside. Jungkook’s mouth fell open in a silent groan, fingers digging into the rug.
Bam started fucking him in short, frantic strokes, pushing deeper each time. The stretch burned, but the heat of it, the raw animal way the dog was using him, made Jungkook’s cock throb painfully against the floor. He could hear Bam’s panting right next to his ear, felt the dog’s hot breath on his neck, the scrape of claws on his sides. Every thrust shoved him forward on the rug, the thick shaft sliding in and out, spreading him open.
When the knot started swelling, Jungkook’s eyes widened. “Oh shit… Bam—” He tried to shift, but the dog locked his front legs tighter and slammed forward. The knot stretched him mercilessly, forcing its way past the tight ring of muscle until it popped inside. Jungkook let out a broken moan, body shaking as the massive bulge locked them together. Bam kept making tiny, instinctive thrusts, grinding that knot against his prostate, and Jungkook came hard without even touching himself, spilling onto the floor with a shaky cry.
They stayed like that for a long time. Bam’s cock pulsed inside him, flooding him with hot spurts of cum that had nowhere to go because of the knot. Jungkook panted into the rug, sweat sticking his hair to his forehead, ass clenching rhythmically around the impossible stretch. Every time Bam shifted, the knot tugged and pressed, sending aftershocks through him.
Twenty-three minutes, according to the clock on the wall. That’s how long Bam stayed locked inside him, panting, occasionally licking at Jungkook’s shoulder like he was trying to be affectionate while still buried balls-deep.
When the knot finally went down enough for Bam to pull out, a gush of cum followed, dripping down Jungkook’s thighs. He stayed on the floor for a while, dazed, sore, and weirdly calm. Bam curled up beside him, looking more relaxed than he had in days.
Jungkook reached over and scratched behind the dog’s ears. “We’re not talking about this,” he murmured, voice hoarse.
But the next evening, when Bam started humping his leg again while he was trying to eat dinner, Jungkook didn’t push him away as quickly. His body remembered the stretch, the heat, the way that knot had locked him so perfectly full.
By the third night, he was already on his hands and knees on the couch before Bam even mounted him, sweatpants pulled down, breathing shaky with anticipation.
It became routine faster than he wanted to admit.
Every evening after work, sometimes even in the middle of the afternoon if Bam got too restless, Jungkook would find himself bent over the couch, or on all fours on the living room rug, or once even lying on his back on the bed with his legs spread while Bam drove into him with that single-minded intensity. He started keeping lube on the coffee table because the dog’s cock was thick and he needed to take it easier some days. He learned exactly how to angle his hips so the knot pressed right where it felt best. He started craving the way Bam would growl low in his throat when he was close, the way the dog’s hips stuttered when that knot finally popped inside and swelled to its full size.
Some nights Jungkook would film it on his phone—propped up on the couch, capturing the way Bam’s glossy black body covered his own, the wet slap of their bodies, the way his own cock leaked and bounced untouched while he got fucked. He’d watch the videos later in bed, jerking off to the sight of himself taking his dog’s knot so deep, moaning shamelessly.
It felt filthy. It felt good. It felt like something that belonged only to them.
Then came the girl.
Her name was Sora. They met at a café near the studio. She was sweet, funny, and pretty in a soft way that made Jungkook think maybe he should try having a normal relationship. They went on a few dates. After the third one, she came back to his apartment.
They made out on the couch. Clothes came off. Jungkook tried—he really did. But when she wrapped her hand around him and started stroking, all he could think about was the thick, hot slide of Bam’s cock, the way it stretched him open so much wider, the relentless animal pace, the heavy knot locking him full for half an hour while cum pumped deep inside.
He couldn’t get hard. Not properly.
Sora was understanding, but Jungkook felt sick with guilt and frustration. That night, after she left, he called Bam over, stripped, and let the dog mount him right there on the same couch he’d been kissing her on earlier.
Bam fucked him harder than usual, like he could smell the other scent on Jungkook’s skin. Jungkook buried his face in the cushions and moaned loud and desperate as that familiar knot stretched him open again, locking him in place, filling him exactly the way he needed.
He knew this was getting dangerous. He knew it couldn’t stay secret forever.
But as Bam’s knot pulsed inside him and another thick spurt of cum flooded his insides, Jungkook couldn’t bring himself to care.
The weeks blurred together after that night with Sora. Jungkook threw himself into the familiar rhythm with Bam like it was the only thing that made sense anymore. Mornings were normal enough—coffee, stretching, a quick walk along the river if the weather was nice. Bam trotted beside him like the well-trained dog everyone else saw, calm and obedient on the leash. But the second the apartment door clicked shut behind them, the air shifted.
Bam would start whining low, circling Jungkook’s legs, nose pushing insistently against his crotch or the back of his thighs. Jungkook stopped pretending he didn’t want it. He’d set his laptop aside, pull off his hoodie, and drop to his knees on the big living room rug without a word. Bam was on him instantly, heavy paws landing on his back, hips already jerking as that slick red cock slid out, searching for heat.
One afternoon stands out in Jungkook’s memory. He’d had a long call with his manager, talking schedules and deadlines, and the whole time Bam had been restless, pacing and mounting his leg under the desk. The second the call ended, Jungkook stood up, shoved his sweatpants down to his ankles, and leaned over the arm of the couch.
“Come here, boy,” he murmured, voice already rough. He reached back with one hand, spreading himself, lube from the bottle on the side table still slick from the night before. Bam mounted him hard, front legs gripping tight around his waist. The first thrust was messy, the thick cock sliding up along his crack before Jungkook angled his hips better. On the next push, Bam sank in deep in one smooth glide, all the way to the swelling knot.
“Fuck—yes,” Jungkook groaned, pushing back to meet him. The stretch was perfect now, his body trained for it after weeks of this. Bam fucked him with that relentless, animal pace—short, powerful snaps of his hips that made Jungkook’s whole body jolt forward. The wet, filthy sound of it filled the apartment, skin slapping, lube and precum squelching every time Bam drove in. Jungkook’s cock hung heavy and leaking between his legs, untouched, dripping onto the floor.
When the knot started to balloon, Jungkook braced himself, breathing fast. “C’mon, give it to me—” Bam slammed forward and the thick bulge forced its way past his rim, popping inside with a rush that made Jungkook’s vision spark white. He cried out, a raw, broken sound, as the knot swelled even bigger, locking them tight. Bam kept grinding, tiny instinctive thrusts that rubbed the swollen knot right against Jungkook’s prostate over and over.
Jungkook came first, shaking hard, cum splattering the couch and floor while his hole clenched and fluttered around the massive knot. Bam followed soon after, flooding him with hot, thick spurts that Jungkook could feel pulsing deep inside. They stayed tied like that for twenty-eight minutes this time. Jungkook stayed bent over the couch, panting, occasionally rocking his hips just to feel the way the knot tugged and pressed inside him. Bam licked at his neck and shoulders, calm now that he was locked in place.
Afterward, when the knot finally shrank and Bam pulled out with a wet gush of cum running down Jungkook’s thighs, Jungkook grabbed his phone. He’d started filming more often. He replayed the video that night in bed—watching himself get mounted, watching that glossy black body cover him, listening to his own desperate moans as the knot stretched him open. He jerked off twice to it before falling asleep.
Their secret life felt almost domestic in its own twisted way. Jungkook started planning his evenings around it. He’d order dinner early, eat while Bam rested his head on his thigh, then clear the table and get on all fours right there on the kitchen floor if he was feeling impatient. Sometimes he’d lie on his back on the bed, legs pulled up and spread wide, letting Bam stand over him and drive straight down. He loved the eye contact those times—Bam’s dark eyes focused and intense, tongue hanging out, while Jungkook stroked his own cock and whispered encouragement.
“Yeah… just like that. Fuck me deeper, boy.”
But the girl—Sora—kept texting.
She wanted to try again. Said she really liked him. Jungkook felt guilty enough that he agreed to another date. Dinner at a quiet restaurant, then back to his place. This time he made sure Bam was in the bedroom with the door closed.
They got as far as the couch again. Sora was on top of him, kissing his neck, her hand slipping into his pants. Jungkook closed his eyes and tried to focus on her soft skin, her gentle touch, her perfume. His body responded at first—half-hard, enough that she smiled and stroked him faster.
But the longer it went on, the more wrong it felt. Her hand was too soft, too careful. She didn’t pin him down. She didn’t fuck him with raw, desperate need. She didn’t have a thick, swelling knot that would lock him full and pump him full of cum for half an hour.
He stayed only half-hard. When she tried to go down on him, Jungkook gently stopped her, making up some excuse about being tired from work. She left looking hurt but polite.
The second the door closed, Jungkook let Bam out. The dog could smell her on him—on the couch, on Jungkook’s skin. It made him more aggressive than usual. Bam growled low as he mounted Jungkook right against the front door, barely giving him time to get his pants down.
Jungkook moaned loud, not caring if the neighbors heard. “Harder—fuck, Bam—” The dog drove into him with punishing thrusts, claws scratching his sides, hips slamming forward. When the knot forced its way in, Jungkook nearly screamed from how good it felt. He came untouched again, shaking, tears pricking his eyes from the intensity. Bam kept him tied for almost thirty-five minutes this time, flooding him until cum was leaking out around the seal of the knot.
After that, Jungkook stopped replying to Sora’s messages as often. He knew what he was doing was fucked up. He knew normal people didn’t crave getting knotted by their dog every single day. But every time he tried to imagine being with her—or anyone—he just felt empty. Nothing compared to the heavy weight of Bam on his back, the burning stretch, the way the knot locked him so perfectly he couldn’t escape even if he wanted to.
One lazy Sunday, Jungkook spent the whole day naked. He worked on his laptop on the couch while Bam rested between his spread legs, occasionally licking at his hole like he was cleaning him up. By evening Jungkook was aching for it again. He set his phone up on a tripod this time, angled perfectly to capture everything.
He got on all fours in the middle of the living room, ass up, face pressed into a pillow. “Come on, Bam-ah,” he called softly.
The dog mounted him immediately. The video caught every detail—the way Bam’s cock slid in on the first try, the fast, wet pounding, Jungkook’s moans getting louder and more broken as the knot grew. When it popped inside, Jungkook’s back arched, a long whimper escaping him as he pushed back, grinding on it.
He came twice while tied—once from the knot alone, and again when he finally reached under and stroked himself through the aftershocks. Bam stayed locked deep, pumping load after load into him until it started leaking down his balls.
Later, after Bam had pulled out and gone to drink water, Jungkook lay on the floor in the mess, cum slowly dripping out of his used hole. He picked up his phone and watched the video, thumb stroking his spent cock lazily.
This was his life now. Secret, filthy, and completely addictive.
He didn’t know how long he could keep hiding it. He didn’t know what would happen if anyone ever found out. But as Bam came back and curled up against his side, warm and satisfied, Jungkook reached down to scratch his ears and whispered, “Good boy.”