As Zack waltzed through his moderately-trashed house, cheap beer in hand, he offered a few waves and smiles to some of the guests. Most of them didn’t seem to pay him much mind. After all, this wasn’t his party, even if it was his house. It was his sister’s, the college-age debate team social butterfly. He was just along for the ride, having dropped out years ago from a mixture of laziness and artistic desire.

“Great party, right?” He sidled up next to one of his sister’s friends, taking a deep sip of his beer. She merely shook her head and lit a cigarette.

“It’s pretty good, but what do you expect from Nina? Girl’s got it all. I see why you don’t.” The callous jab was enough to put the brunette on the defensive, but he could barely manage indignant grunts as rebuttals. He finally settled on polishing off his beer and crushing the can, tossing it to the floor as he stormed off in search of some other hangout or hookup.

His pouting march brought him face to face with his sister, and she seemed far less irritated than he was. “Hey, Zack. Doing alright? Music isn’t too loud, is it?”

Compared to her somewhat jockish brother, Nina was deep into her own little punish subculture, her tan arms covered in tattoo sleeves. Her freckle-kissed face was largely made up, with swirling eyeliner and pitch black lipstick framing her caramel-skin in an almost malevolent way. Her hair, clipped short and uneven to fit her air of walking chaos, was freshly washed and fluffed into a haphazard bob. While he had decided to present himself to the house party casually, in nothing more than pajama pants and a hoodie, Nina had dressed ornately, a leather jacket covering the upper inches of a tight, hip-hugging skirt, her hands covered in bangles and bracelets. There were striped knee-socks over her legs that seemed to guide one’s eyes up towards her modest ass, the only part of her that wasn’t really exceptional. Zack almost felt bad for ogling her, but he was just drunk and frustrated enough to neglect his misgivings.

“It’s not. Wish your friends weren’t such bitches.” He said rather coolly. Nina shrugged, unwilling to deal with her brother while he was pouting, and made her way to the living room, which was rather smoky from a smuggled hookah atop the coffee table.

Instead, Zack headed out the back door and rested beside their hot tub, continuing to smoulder from his lack of ability to pick up a good time. He was hoping that Nina would at least talk him up, or do something to make it worth his while for helping her set up. But she was treating him just like all the others. He couldn’t help but to wallow, watching the college students live their lives while he kept himself from living his.

Pretty soon, though, his solitude was pierced by a pair of girls, both similar in aesthetic to his sister. They were far paler, but they shared the same pitch-black hair, piercings, and emphasis on jet-black, angled apparel. “Hey, you’re Nina’s brother, right?”

“That’s right.” He responded.

While one of the girls passed him a beer, the other one lit a cigarette, and they began to talk him up. They were someone distracted throughout the conversation, but they remained friendly, and their demeanor helped Zack to talk openly. That was, until he started to vent about his sister. He didn’t even realize it was happening. At first, he was thanking them for hanging out with him, and it quickly pivoted into an unsubtle bitch about the party and his sister’s neglect of his needs.

One of the girls, the one drinking, quickly excused herself, and Zack went silent. The other one finished her cigarette, and withdrew a little lipstick. Zack eyed it oddly; the tube was almost carved out of some gem, and it radiated light in the cool night on its own accord with nothing to reflect off of. She painted a couple more layers of lipstick on her mouth, smacked her lips together, and leaned forward, grabbing the brunette by his tattered hoodie. She slammed her lips against his, and moaned softly as she moved her mouth, smearing his lips with the excess makeup. Stunned, all that Zack could do was kiss her harder. She pulled away, and grinned at his befuddlement.

“You sound like you need a good change of pace… Some people say a witch’s kiss can do just that… See if it works for you, okay?”

With that, she left him, and a still stunned and frustrated Zack was permitted to return to his sour attitude, waiting out the rest of the party in his little corner. When the moon was beginning to sink back into the horizon, he finally pulled himself up and stomped back in, heading back to his bedroom. The thrumming music had long since been cut off, and the piles of cups and cans were an issue for the morning. Marinating in the silence, he stomped his way up the stairs.

He realized that the door to his sister’s room was open, and he heard the low sound of lips smacking together. His curiosity got the best of him, and he peered into the door. What he saw was nowhere near what he expected; his sister was in her bed butt-naked save for her stockings, laying on her stomach with her ass raised upwards. Sitting on the edge of the bed, nose pressed into his sister’s deep caramel hole, was the smoking goth girl from earlier. Suspecting that she was being watched, she pulled away, smiled at Zack, and took her leave.

“Fun party. Be seeing you around.” She stepped away, her heels clacking behind him as Zack continued to stare, dumbfounded. His sister didn’t move at all, save for the slightest little snore. He stared at the cleft of her cheeks and her dark hole, and watched as the tight, textured ring winked needily in his general direction. He saw the thick smears of black lipstick around her hole, clearly delineating her anal ring.

“W-Why’d you stop?” She whined out, her voice differently-pitched and completely addled. Instantly, he knew that she wasn’t awake enough to care about anything but pleasure. While he wasn’t going to push things further, he knew that he would be able to sneak a taste without her any the wiser. And, after all, he reasoned with himself, so frustrated and drunk that he revelled in his own sleaziness, didn’t she owe him for setting up the party?

He stepped in quietly, and took the goth’s position, pressing his face towards her anal cleft. He wordlessly pressed his own lipstick-stained lips against her asshole, practically ghosting over her skin. At this moment, he felt a twang of regret, and moved away, trying to hurry away from the situation, but Nina sleepily reached back and grabbed his hair, slamming his head forward and against her cheeks. His body moved on its own accord, his tongue peeking out and wedging itself into her already slobber-lubed shithole.

His eyes widened but he forced himself to remain silent, even as his sister giggled and ground herself against him. Zack tried to pull himself away, but his sister wasn’t having any of it. The goth simply held him where he was, and he was forced to wrestle with the longing that rose up in his chest at it.

He held the smooching position for nearly ten minutes, only hesitating again when his lips became incredibly numb, and he felt a sort of sucking ache on his face. He felt her hole puckering and flexing against him, and at first wondered if he was overstimulated, but then she mewled, and pressed him further forwards, and with a wet slurping noise his tongue was tugged further into her tubes. He tugged himself away, frantically, realizing that something didn’t feel quite right, but the sudden motion made him lose his balance. Not only did he fall backwards, but he knocked Nina backwards off of the bed.

He couldn’t see it, but the black lipstick on the two rings of muscle had hardened into a unifying waxy layer that seemed to be holding them together like some sort of magical super glue. His hands, which had reached up onto her ass cheeks to desperately find some support to tug himself away, instantly sank into her freckled butt, only the lowest joints of each knuckle remaining intact. His attempts to struggle only permitted the digits to sink deeper, at which point they were erased completely.

When she tumbled backwards atop him, her ass rippling as she smushed him beneath her cheeks, Zack was overwhelmed with a sudden tightness, a smothering warmth that made the world sound as though he were experiencing it underwater. His entire face was fed right into the spasming pink flesh of her inner hole, his cheeks being spread apart around the area and fattening the inner parts of her cheeks. His legs kicked desperately, and he prayed in some thoughtless oblivion that Nina would notice that something was wrong. Whatever hate or punishment he earned would be better than this.

But, Nina didn’t notice anything wrong. Grumbling to herself, she rolled over and tried to pull herself to her feet. Zack felt his neck being tugged upwards, his body going limp behind her hole. His weight was enough to make her stumble again, and keep her addled form from being able to climb back into her bed, but rather than investigating the oddity Nina simply cursed under her breath and tumbled back down, the impact feeding Zack’s shoulders into her ass. The soft, almost claylike flesh was speared apart by his intrusion, only to slowly spring back to its previous form, creeping over his body as though it belonged inside of her. Every part of him that vanished inside of her was subjected to an electric tingling, followed by a complete loss of feeling as his structure was tugged apart and reduced to thick fat cells to contribute to her gain. Then, over the course of the following minutes, his sensation would be reignited in an entirely alien way, his nerves tuning back in spread in layers over her fat goth cheeks.

“Nngh… Who’s back there… feels pretty good…” She mumbled out, before drifting even deeper into her drunken sleep. Zack managed a singular, terrified kick against the floor before his body spasmed and went limp. His nerves reconnected to operate only her gluteal muscles, all his other motor knowledge baked away into whatever beer-brewed farts were still festering within her bowels. As he tried to thrash, he only managed to make her ass shake enough to clap, sending further transformative ripplings through his body. His torso was tugged in and spread apart in all directions, his lighter skin tone darkening into her toasted caramel shade. Barely any of his freckles were retained within her new backdoor heft. The only thing that carried over was a small wine-stain birthmark that had been on his lower back, which was now along the space bridging her left ass cheek and her thick thigh.

Zack was in a true panic, but the powerlessness made any opportunity for escape absolutely useless. To make matters worse, his connection with his sister’s body was ensuring that Nina’s intoxicated state shifted onto him as well. As his new derriere body began to feel heavier, his mind slowed and his sense of panic withered away, replaced by an over-imbibed exhaustion. Zack felt his mind actively being dragged down beneath the fatty undertow, and he fought it with all of his might, but there was nothing he could do. Before his body was entirely consumed his consciousness faded away alongside his sister, the tingling fading into white noise as he was tugged further and further into his new form.

Over the coming hours, as the moon drifted down onto the horizon and the sun rose, Zack’s occasionally twitching lower half was tugged inwards to her ravenous hole, his clothes vanishing alongside the rest of him. His legs were folded inward, his shoes drifting into the anal chute alongside his feet, as what little imprints remained of him sunk into her thighs, fattening them enough that her sudden anal endowment still fit her frame. Her hole spasmed a few times once he was entirely gone as though to mock or punctuate his disappearance, the motion serving as some sort of rousing shock to his consciousness.

When he came back to himself, his existence centralized around her bowels, Zack was still fuzzy and almost completely incoherent, his mind full of fragmented thoughts and desires. He dwelled in blissful ignorance as the sun rose into the morning sky, his consciousness somehow perceptive of the warming sunlight.

However, as Nina finally came to with a jolt, she bit her lip and greeted the day by forcing out a truly rotten, rippling fart. As the spicy scent and taste rushed out of Zack’s new form, it was as though he were greeted with smelling salts. His mind realigned, and he was instantly hit with the humiliating horror of his new form.

He tried to scream, to call out to his sister and beg her for some sort of salvation, but the only thing that Nina became aware of was an itchy tightness deep within her butt. She arched her back, curled her toes, and blasted out another wet stinker, the vibration making Zack desperate to gag and cleanse the taste. But he was unable to move at all. He felt a thick lump in what was tantamount to the back of his throat, and he tried to hack it up, but he barely managed to get his oversensitive lips to twitch. The motion was enough to force it forward, and as a result Zack clung to what control he did have.

Pulling herself to her feet, and groaning at the odd feeling in her ass, Nina grabbed for her skirt and tried to pull it up, ignorant to the fact that she wasn’t wearing panties. However, it proved impossible to get her skirt up beyond her thighs.

“Wait a minute… This was too big last night, what happened..?” She asked herself, but before she could get far there was an odd flicker around her. Suddenly, her lips were covered in the other girl’s black lipstick, and the skirt was easily able to be tugged around her butt. It was still short enough to really show off her new globes, though.

As she stretched and tried to work out the kinks in her neck that sleeping on the floor had gotten her, another deep desire to fart made itself known. Squatting slightly, she placed her hands on her gut and pressed.

Instantly, Zack felt a wet lump leaving the anal ring, and alongside the particularly raunchy fart, his clothes came sputtering out, his hoodie and jeans wet with anal mucus, crumpled into thick balls, and stained with brown streaks. As the goth girl fanned the air, however, there was another feeling for her as though she were being jolted. Another fart blasted out of her even louder than the last, enough to actively startle her.

As the gas exploded out of Zack’s body, the taste even raunchier than the past ones, leaving the faintest hint of rancid beef within the aerosol fertilizer, it washed over the ruined clothes. The gas seemed capable of dissolving the fabric, as the rippling air actively began stripping away colored particles of his clothes. The gust of rectal wind carried his clothes apart into colored clouds that soon spread apart so thoroughly that they were completely unidentifiable, and Nina noticed absolutely nothing wrong.

Zack, for a split second, felt his mind go blank, and he was somehow made aware of his clothes vanishing from existence. He didn’t have ever-present sight, but he was cursed with that momentary awareness, his mind shrieking from the confusing surrealism of it all.

Nina turned around just after his clothes were split apart, and sniffed the air, fanning it. “Ugh, what the hell did I eat? Fuck, it was that shitty beer. I should have told Zack to buy the good shit.” Another jolt of energy left the goth and her ass both disoriented. “Wait a fucking minute… Who the hell is Zack? I don’t know any Zacks on campus…”

As Nina reached back to scratch her ass, her fingers spreading her brother’s repurposed lips open and stimulating him, Zack balked at her words. She had to just be mad at him. She knew where he was and was rubbing it in. However, she certainly was committed to the act, especially given her lack of comment as to his clothes actively splattering out of her shithole.

He tried to suck on her finger to try and communicate somehow, but she was scratching hard enough that he couldn’t hold a coherent position. In fact, static edged against his mind from the stimulation. She pulled away and callously sniffed her finger, wincing at the odor.

She pulled away and went about her morning routine from there, sipping a freshly-brewed coffee as she bagged up the loose cans. “Ugh, it sucks I’ve got to clean up on my own. Had to set up on my own, too. I need better friends.” Again, there wasn’t a single mention of her brother.

“Wait a second…” Nina paused, walking over to the fireplace. She picked up a family photo, only to notice that next to her mother there was a thick, person-shaped stain. “What’s this? Who smeared candy on the picture?”

Again, Zack was cursed with an awareness of exactly what she was looking at. He was granted a vision of their family portrait, showing the siblings with their parents. However, he watched in real time as his image was suddenly snapped away, replaced with a silhouette-shaped sugar stain. It was easy for the frustrated goth to scrape away, and she wiped the dirt off on the back of her thigh, inadvertently marking Zack with another piece of evidence as to what was happening to him.

However, as she picked everything up, the goth returned her attention towards getting ready for the day. She pulled a tight thong up , and tucked it beneath her skirt, the fabric wedging itself uncomfortably between Zack’s lips. As a side effect, it made every little brap from her still-present bout of gas even louder, serving to spread the sound over a wider area. As that specific piece of her thong was subjected to point-blank ass-blasts, it took on the smell of her gas, forcing Zack to marinate much closer to an ever-present reminder of his fate.

The next few hours were numbingly slow and uneventful, as Nina lazed about and waiting on the afternoon to come. He was forced to flex himself just to keep some stimulation, an act that coaxed even more little toots out of him, every attempt to maintain some autonomy reinforcing his status as goth girlbutt.

Finally, though, she hefted herself up and prepared for class, slinging her bag over her shoulder and leaving the house, actively walking along the sidewalk. The motion was enough to fully disorient Zack, giving him something akin to a headache with every bouncing motion. She was finally thick enough for her ass to actively bounce with every step, and as she broke into a jog to ensure she made it in time, her ass actively clapped. At the sound, Nina felt a momentary surge of pride at the sound, only for that to regress into confusion; after all, her ass had always been this big. Why be proud of it now?

She made it to class with time to spare, and took her front-row seat, leaning down and focusing on her phone as she waited on the lecture to begin. Meanwhile, Zack was pressed down against the cheap plastic, his form contorting and his thoughts splitting as her panties rode further up her crack, creating a consistently distracting little ache. She shuffled back and forth to try and work it out, but the motion only forced another pressure backing up her bowels further down. Before the lecture could even start, a low rumble in her lower gut sent her scampering out of her chair and towards the bathroom.

Zack was granted a flickering image of the toilet bowl mere seconds before the goth’s bare bottom pressed against the cold porcelain, the scent of toilet water and artificial lilac freshener instantly adding themselves to the permeating smell of gas that clung to him. He felt his lips puckering, and a sudden protrusion threatening to spread them apart. As he tried to resist, he found that even that miniscule fight was now impossible. His mind was wracked as the disgusting taste of the smooth coil rushing through her colon as it finally crowned, his lips yawning wide enough for the greasy brown to sag down towards the water.

Nina groaned and pressed her gut down against her thighs, flexing her hole in an effort to pinch off the fat loaf. Post-hangover shits were always particularly rancid, greasy and slick and yet unwilling to fully come out. It was a fight for sure, and Zack was reduced to a passive observer, his senses dulled and yet flickering into hellish oversensitivity.

Nina remained silent save for a few sighs and squeaks as the hot turd worked its way out of her, mostly composed of whatever parts of Zack couldn’t be attuned to the rest of her body. Her brother tried to retch at the taste again, and for a moment he was granted a reprieve as a quick flit of gas forced the turd to break off, plunking down into the bowl and splashing a bit of cold water over his form. However, it proved only the lead-up to a worse experience; the thin, bright brown of booze-bolstered ribbon shits.

They sputtered out of him in thin strands that broke apart in the bowl, astoundingly hot against Nina’s sensitive hole, and more rancid than anything she had let out before. That itself was enough to almost entirely shatter Zack’s mind, simply as a coping mechanism for him to endure the humiliation. Somehow, despite his lack of understanding as to what was coming out of him, he was struck with the sudden understanding that there was no coming back from this. A sudden wash of hopelessness convinced him that this existence was better than no existence, especially as he reviewed the incidents in which his presence had been scrubbed from Nina’s mind and their house. Against all odds, he forgave the goth, and hoped that she’d get some good use out of him.

With one last sputtering fart his consciousness was ebbed away, replaced by an auxiliary understanding of himself as a hole distanced enough from the cruelty of his new life. He found stupid satisfaction as her ass barked out a few finalizing farts.

The last of which, however, spat out a stained phone that was otherwise intact, somehow separated from the pants that sputtered out earlier in the morning. She fished it out of the bowl, and eyed it curiously, trying to puzzle out why she hadn’t noticed it beforehand. Just as her head throbbed with the ache of trying to understand, it rang. She dropped it, startled from the sudden movement, only for it to actively splatter into cubic chunks against the ground, which then melted into the tiled floor. She eyed it with surreal confusion, before there was one more jolt of energy that glazed over her eyes. Forgetting that it had been an experience, she wiped Zack’s mouth clean, making his dumbed-down mind purr with pleasure, and pulled her panties back up, the thong providing the slightest stimulation for her satisfied butt.

Once she washed her hands, she left the bathroom, and headed back towards the class. But, before she got there, she noticed one of her classmates staring longingly at his phone. Something told her that he was waiting for some sort of change. His expression didn’t indicate any sort of happiness.

So, acting on some odd instinct, she walked over to him and offered him a peck on the lips, spreading a few specks of her black lipstick onto his mouth. She offered him an affectionate smile, and turned to return to her class.

It was that incident that clipped whatever lingering threads of consciousness remained in her butt, whatever otherworldly energy that had permitted the change leaving her and transferring over to her classmate. Zack was completely thoughtless now, not even those simplistic longings present within his existence, his mind almost perfectly blank as an ass deserved to be.

“You looked like you needed a pick me up, buddy!” Nina grinned at him. “Maybe a witch’s kiss will bring you the change you need. It’s just a superstition.”

A little toot escaped her as the world jolted again, and his eyes glazed over from the experience.