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Desmond was dealt fate's cruelest hand that he could have imagined. And it came to him in the form of two words: pancreatic cancer.
Getting diagnosed with it was already a death sentence, even with today's advancements in medical science. But by the time he realized he had it, the cancer had already become thoroughly entrenched in his body and spread to his other organs. Even worse, he had no health insurance, and the money he could've spent for treatment had already been sunk into occult paraphernalia.
If any of it worked at all, it was his ticket to a new lease on life. And he knew what kind of ritual to perform.
As Desmond cleared out space in his living room to perform the ritual, coping with the dull pain around his gut, he found a masochistic mirth in it all. Not because he enjoyed his condition but because of where his life had gone to get to this point.
Desmond still remembered what got him into the rabbit hole of demonic mythology. There was a cute girl in college. He was desperate; she invited him to join her in a demon summoning, and he accepted. Desmond didn't take it seriously until, to his surprise, a crimson succubus appeared in her dorm room.
From what he was told, her name was Katoris. But seeing her in person, she was astonishing. At least as far as his initial impression of demons went.
Katoris had beautiful red, leathery wings that spread out to be as wide as she was tall (standing at a whopping 7'2"!). Surrounding the base of her horns (which pointed forward in a sideways S-shape), Katoris's hair consisted of dreadlocks that went low enough to reach her shoulder blades yet not so far down that it interfered with her wings. She was also completely naked, exposing breasts as big as her head, eight-pack abs, and a flaccid cock that eclipsed Desmond's erect length and width.
Katoris focused her gaze on the goth girl and grinned. "Ah, Fiona! It's so good to see you, as always."
What surprised Desmond was how he heard Fiona giggle despite being the most emotionally vacant and deadpan girl he knew.
"Likewise!" Fiona cheerfully replied, greeting Katoris by fondling her full, heavy scrotum with the same cordiality as a hug between best friends. Fiona had to use both hands since each of those demonic testes was larger than a softball.
"Um..." Desmond had to swallow his pride and choke down the envy he felt. Katoris was beautiful, and from how Fiona flocked to her, there was no chance he was getting laid tonight. "You two know each other?"
Katoris glanced at Desmond. Her gold-on-black eyes glowed in the dim, candle-lit dorm. And he felt her looking at him and at his soul. Desmond knew he was an open book to her. But it wasn't until his study of demons started that he figured out where this feeling came from: succubi can see things about people at a glance, such as sexual orientation, libido, kinks, and even their disposition.
With a smile, Katoris answered, "We do." She felt Fiona greedily slurping down her half-erect cock, which throbbed and lurched further down the goth girl's throat and bulged it out. "And who might you be?"
"D-desmond..." he nervously answered.
"Nice to meet you, Desmond," Katoris greeted. "Since you've taken the time to help my precious toy,"—she placed a hand on Fiona's head to illustrate who she was referring to—"I'll assume you know who I am."
If it weren't for the fact Desmond barely knew the girl he was hoping to get lucky with, he'd feel heartbroken. "Your name is Katoris, and you're a succubus."
"That's the basics, yes," Katoris confirmed. "You were hoping to spend time with this girl, weren't you?" When Desmond chose not to say anything, she assumed it was an admission. "I'm willing to share her with you, you know. For a small price."
"You mean my soul?" Desmond bluntly asked.
"I'm not going to force you into a pact, Desmond," Katoris assured. "And I'd be disappointed if you pledged yourself to me just so you could keep Fiona's bed warm while I'm not around." She bit her luscious lower lip as Fiona started deep-throating her. "You really did miss me, didn't you?"
Fiona's only response was to give a lewd moan. She wanted to focus entirely on pleasuring her Mistress, and she would only stop to take in air.
"I missed you too, sweetheart," Katoris replied.
"Did you make a pact with her?" Desmond wondered.
"Oh, not at all, surprisingly!" Katoris answered. "She didn't have any big wish for me to grant. She summoned me so she could drink in my beauty and satisfy my urges."
"You... grant wishes?"
Katoris shrugged her shoulders. "The mortal soul is a priceless commodity worth moving mountains for. It still has to be something within reason since my powers can only go so far, and it shouldn't be something that'll destroy reality. But other than that, the more ambitious the wish, the better!"
Desmond slowly nodded his head as he contemplated the idea. "... If anything comes up, I'll let you know."
"Sure," Katoris responded. She placed both of her hands on Fiona's head. Fiona immediately recognized what was about to happen and brought her arms around Katoris's thin waist, bracing for her mouth to be used like a fleshlight.
"Take as much time as you need," Katoris continued, thrusting her hips as the sound of her balls slapping against Fiona filled the room. "My immortality makes it so I can wait as long as it takes for you to come to a decision. Or not. Until then, you're welcome to stick around and watch. Maybe even beat your meat to me plowing my toy. You won't mind if he watches, do you, dear?"
"Mm-mm." Fiona had no issues with this.
"Thank you both, but..." Desmond sighed. "I really need to do some homework..."
The experience was valuable to Desmond, despite leaving the dorm room humiliated and aroused. Still, Katoris's immortality... The doctors said Desmond only had a month left to live, and if he could pull this off, then he'd defy the doctor's expectations by countless eons. So what's the harm in giving away something he'll lose to the cold oblivion of death, anyway?
Desmond hadn't forgotten the process Fiona showed him. Even after a decade since college, he knew how to draw the summoning circle, how many candles had to be used, and how dim the room needed to be. The only thing that gave him trouble was the correct syllables to say, but he had reference material that gave him a refresher.
After a full minute of chanting, he watched as a portal appeared on the hardwood floor, where Katoris dramatically rose into the material realm. She was exactly as Desmond remembered: incredibly tall, curvy, strong, and hung. Being on his knees made her appear even more imposing.
From Katoris's perspective, she saw a familiar face. It was tainted by the onset of jaundice, but she recognized who he was.
"Desmond..." Katoris frowned as she put the pieces together. She could see time was running out for him. "You're dying."
"Not if you can help me," Desmond told her as he stood up. "You said you can give me anything I want in exchange for my soul, right?"
"Within reason," Katoris replied. She nodded slowly and added, "But I think I know where you're going with this. Immortality?"
Desmond's expression remained serious, if not outright determined. "Immortality," he confirmed.
Katoris smirked. "You know, you aren't the first man or woman to fear death. I will help you, but it will cost more than you realize."
"I'll pay any price. I just—"
"Desmond, you don't understand," Katoris interrupted. "This isn't a matter of the soul anymore. Your entire identity will be at stake. Once we commit to this, you will no longer be who you are. Your life as you know it will be forfeit to me. Now, as I said, I can help you. But there's also no shame in having the dignity to live out the rest of your life to your fullest before dying happy."
Desmond paused as he considered her words. He was still determined to be cured and become immortal, but the fact that Katoris was trying to talk him out of it felt strange. "... Do all demons try talking people out of forming pacts, or is it just you?"
Katoris laughed at Desmond's comment. "Pacts are the ultimate commitment, Desmond. It's not something to be taken lightly. Besides, I'd rather not hear your whining if you change your mind after the pact is finalized."
"I'm not going to change my mind on this." Desmond took a step forward and stared up at Katoris. "You said it yourself, I'm dying. But I'm also still in student loan debt after a decade of making less money than I hoped. There is **nothing** to go back to."
Katoris couldn't remember when a mortal felt so desperate to escape their life and problems. Of course, Desmond had every justification: his life was miserable, and fate gave him a healthy helping of cruelty. But her train of thought was interrupted when she felt a pair of hands fondling her balls. She looked down and saw Desmond acting boldly.
"I still remember what happened in Fiona's dorm room," Desmond commented. "It intrigued me enough to study demonology." He then gave Katoris a smile for the first time since they met. "So I know how to bribe you with a good time."
Katoris didn't mind the attention. In fact, she was already becoming stiff while her balls audibly gurgled and groaned with anticipation, all from Desmond's touch. A lot of blood had to rush in, making the process slow and steady. The veins along her cock started becoming thicker as blood trickled in, causing an erection to slowly lengthen and rise.
"You do realize what happens next, right?" Katoris commented.
"Yes," Desmond flatly replied. "I was there, Katoris. I've actually been practicing using—"
"No, not that—although I do appreciate you being prepared," Katoris interjected. "This pact will mean you'll become a succubus, like me. And I'll have full control of how you'll come out since, technically, you'll be subservient to me."
Desmond stopped to consider this information. He knew he was getting himself into a commitment, and he heeded her earlier warning that his life would change. But he didn't realize he would end up as a succubus. Desmond took a moment to look over Katoris's physique again.
"So I'll turn into something like you?" Desmond asked, returning his eye contact to Katoris. "Wings, horns, everything?"
Katoris only nodded to him as her mischievous smile grew.
Desmond didn't break eye contact with her as he grabbed her behemoth of a rod, brought the head into his mouth, and eased himself down until his lips pressed against her pelvis.
Katoris shivered as she watched Desmond disappear beneath her large breasts. She didn't need to see what was going on; she felt his tight throat trying to strangle her half-erect cock instead of the other way around. She felt things get even more cramped as her member throbbed harder inside Desmond's esophagus. It stretched his throat to new limits as it burrowed deeper into his throat, peaking at fourteen-and-a-half inches long.
"Such an eager thing~!" Katoris cooed. She placed her hand on Desmond's head as her sharp, talon-like nails gently stroked his hair like teeth on a comb.
Then Katoris sensed something else within Desmond: usually, men would be repulsed by servicing another woman who happened to possess male genitalia. But Desmond, she realized, was as hard as a rock. His endowment was almost painfully average, barely hitting the six-inch mark. This gave her an idea.
"You know what? Something tells me you won't mind if I were even bigger than I am now," Katoris mentioned. "And since you're already going to become my plaything, it'll be wasteful to have all those inches disappear. You know where I'm going with this, don't you?"
Again, Katoris felt a stirring within Desmond. Her pheromones were getting to him. Or he thinks she's a genius, and her smarts were turning him on even more. Either way, she knew she was worming her way into his heart.
"Of course, you'll get something out of it, too," Katoris continued, stroking his hair some more as she wanted to tease him with the fantasy she found herself forming off the cuff. "I'll give you a body that'll make mortals cum at the sight of you. The perfect pair of tits, a body strong enough to manhandle anyone you want, an ass to die for... and, of course, a pair of thick, plump lips that'll let you suck any cock dry, including mine. You'll need that, too, since... Well, you've done your homework, so I'm sure you know."
"Mm-hmm!" Desmond could only hum in acknowledgment. He found herself in Fiona's position now, becoming hungrier and more eager to suck Katoris's cock, all just to get a taste of her demonic semen. His dick, inferior to his guest's size, quickly became rock-hard and tented the pants he wore.
"Thought so," Katoris replied, then continued: "But does that sound good to you? Becoming a succubus who loves giving head to her new Mistress~?"
Katoris's body received a jolt she hadn't experienced in so long. It brought her back to when she was nothing more than a neophyte. This was before she was ever given the rod that hung between her legs.
Katoris's first-ever prey caught her by surprise, just as Desmond did. "Lesley" was his name before she helped him become a woman, who now goes by "Leslie." Leslie was a nubile, effeminate specimen who was just as eager for pleasure, just as willing to give up her tool. Although she failed to claim the mortal's soul and grow more powerful (if she could go back and do it all again, she'd take her soul first and then grant her wish later), Katoris made someone happy.
Once Katoris remembered to form pacts with people beforehand, she devised a way to use them to enrich people's lives instead of oppressing them, which gave her a reputation as one of the more compassionate demons to exist in the Nine Hells.
But she couldn't feel nostalgic about her past since her brain was too busy processing the most intense, pleasurable head she'd ever received. "B-by Lillith, you're somehow better at this than Fiona...!"
Katoris failed to retain her composure and the air of being a sexy, imposing, mysterious demon lady. She forcefully grabbed Desmond by the head and forced him to bob his head up and down her length. Instead of fighting against this, however, Desmond let it happen. He almost gagged on her meat monolith, but knowing how perverse succubi (and incubi, by extension) can be, that would only serve to turn them on even more.
"That's it! Milk me until every drop of my essence is swirling around in your body! Make yourself mine! Submit to me!"
After a minute of pleasuring Katoris, Desmond had his head forced down until she was balls-deep in his esophagus. With his chin placed on her impressive testes, he felt them flex as they emptied their combined load directly into his stomach. With her cock occupying his tongue, Desmond couldn't taste any of her seed, but he could already feel her semen's effects on his body.
The pain that plagued Desmond had already vanished with the first rope pumped into him. He felt his physical appearance begin to shift as well, yet it felt as wonderful as the orgasm Katoris experienced. He closed his eyes as he found himself unable to resist ejaculating alongside Katoris.
But with each spurt of cum he let out, Desmond's tent got shorter and shorter until it appeared as though he were flaccid. However, the truth was far stranger: in place of his dwindling manhood, it inverted to become a fully-functioning vagina and uterus. His nose shrank until it became button-like, his jawline got thinner, his hair grew longer, and his frame shifted to resemble an hourglass.
But what distracted him from the sensation was how Katoris's cock continued to lurch down his esophagus, even thickening up and stretching his inner walls as the bulge along his throat became more pronounced.
*Is it getting bigger!?* Desmond wondered. He could feel it, but he had to see this just to be sure!
Right on cue, Katoris gently pushed Desmond back and pulled her cock out from his mouth. And, as it turned out, he wasn't imagining things: that crimson spire looked meaner than he remembered. It was almost twenty inches in length, as thick as his arm, and her balls had each thickened by an extra inch in diameter.
However... all of her looked meaner, too.
Katoris stood half a foot taller, with a body bulked up with more muscle and definition than she had at the start. Her eight-pack abs became much more pronounced, with the hillocks and valleys further emphasized to look indestructible. Her legs were akin to tree trucks that could hold anyone's head in place and keep them there with a supernatural vice grip. Her arms, one of which she held up to give her bulky bicep a nonchalant flex, told a similar story; nothing could stop Katoris from manhandling any mortal she wanted. Even her horns looked bigger!
"What a rush!" Katoris exclaimed, her voice notably lower and more sultry. "It's been a while since I encountered someone like you. But to have a soul such as yours..."
"So you did... it...?" Desmond brought his hand up to touch his throat. He noticed how strange his voice sounded, but then he realized her digits felt daintier than he remembered. Desmond looked at both of his hands. He was happy to see his jaundice had gone away, but he wondered why his hands had a womanly shape and softness. Desmond felt his face and noticed differences there as well.
Katoris wanted to skip past the dramatic reveal and told Desmond plainly, "If you're wondering why you sound weird, it's because I sucked out every last drop of your masculinity along with your soul. So, congratulations, **Destiny.** Not only are you immortal, but you're a woman now."
Destiny froze, and she swallowed in a dry throat. She stared at Katoris's fattened cock, then reached her hand down to cup her groin, only to feel nothing. "N-no, that can't be—"
"You asked if you would turn into something like me, and I said yes," Katoris clarified. "You're already halfway toward becoming a succubus."
Logically, Destiny knew what was happening and heard Katoris say the words. It was her heart that was still in disbelief. She stood up and quickly walked to her bedroom and into the master bathroom without saying a word. Once she turned on the light, she saw it all.
Destiny was a girl now. Her reflection felt like she was looking at a different person, one with long black hair, a pretty face, and a slim figure that made "Desmond's" clothes look baggy. Destiny could see herself falling in love with the girl before her if she wasn't simply a reflection in the mirror. Maybe "Desmond" could meet someone like her at a bar or the library if he hadn't been diagnosed with cancer.
What a life that would be... to wake up to a woman wearing "his" clothes because she felt more comfortable in them than whatever she had hung in her own wardrobe.
Destiny's reminiscing and fantasizing disappeared when she saw Katoris walk up behind her. Her massive member had enough weight that it had its own sway—its own swagger—with each step she took. With a mischievous smile, Katoris reached down to grab Destiny's shirt collar, then ripped it vertically in half. She did so with the ease of tearing a sheet of paper in half, which made Destiny jealous of Katoris's strength. But more than envy, however, was disappointment. Destiny looked at the tattered remains that slid off her arms and fell to the floor.
"... That was my favorite shirt," Destiny commented.
"Was it?" Katoris wondered. She delicately traced her fingers along Destiny's rejuvenated body, which shuddered in response. "It looked rather plain to me."
Destiny found herself getting aroused by Katoris's presence and her touch. She leaned against the demoness, their height difference placing Destiny just below Katoris's full, perky mounds. But the erection that slipped underneath one of her arms made their positioning feel awkward. Yet she couldn't say she didn't feel the temptation to touch it, then stroke it with the affection one would deliver to a pet reptile.
"Yeah, but it's my favorite color, and... I don't think they make the ones with pockets on the front for women."
Katoris hummed briefly yet thoughtfully. "Hm... So you like blue, then?" She then proceeded to undo Destiny's pants and strip her down to nothing. "Lucky you; mortals converted to demons tend to be some shade of blue."
"And red ones are natural-born demons, I know," Destiny replied. She looked down to stare at her own reflection as she was undressed. "You said I was only halfway to becoming a Succubus, right? How come I look so plain?"
Katoris giggled at the question. She got closer and whispered in Destiny's ear, "That's the fun part. You won't be once I'm finished. You're going to be the sluttiest little demon to ever live. And my personal toy to empty my balls into."
The acoustics in the bathroom made it easy for Destiny to hear the gurgling from Katoris's hefty balls. Destiny wasn't sure if intuition told her or if instinct was responsible, but she could tell Katoris was hungry for another round. But, just in case either of those aspects failed her, she'd also realize what was happening when Katoris reached one of her muscular arms around Destiny's waist and carried her out of the bathroom like a cat. After casually throwing Destiny onto the bed, Katoris climbed on top and positioned herself so the palm-filling head of her cock was barely touching Destiny's virgin cunt.
Destiny nervously looked up at Katoris. "Is this going to hurt?"
Katoris gave a sweet smile in response. "Oh, sweetie. It won't hurt unless you want it to. And I can tell you aren't that type of person. I promise you'll love it."
Destiny still felt uneasy, but she did smile back. She spread her legs and readjusted herself to get comfortable, which prompted Katoris to gently slide her dick inside.
Destiny let out a gasp when she felt Katoris's entry. The sheer volume of succubus meat that went into her was incredible! Katoris's endowment broke through the hymen, then somehow went through her cervix, and she was currently "wearing" Destiny's womb like a condom. This shouldn't feel this good—it shouldn't even be possible for something like this to happen! Yet she lay there, her body paralyzed by the pleasure that made her body seize up and her toes curl.
When Destiny did let out a moan, it was shaky. "H-holy fuck...!"
"See? You're already getting all the perks," Katoris commented. She was balls deep in Destiny, but she didn't move. She just admired how much her cock made such a brazen bulge, how it looked like it was gravitating toward Destiny's mouth, and how easy it was to see it throb. That same throbbing made it difficult for Destiny to focus since each one sent waves of pleasure that crashed along her body. "If you were still a regular person, I would've split you in half by now."
"So I'm—ah!—changing?" Destiny wondered.
"You already have been, ever since you swallowed my cum," Katoris answered.
For some reason, this only got Destiny more hot and bothered. She shouldn't be turned on by how much she's giving up for the sake of living forever, but all the teasing and stimuli were almost calculated to bring out her darkest, most lecherous side.
"Everything about you belongs to me now," Katoris continued. "Your body, your mind, your libido, all of it. It's only a matter of time before your world sees who you belong to."
Destiny's heart was practically beating out of her chest. Lust clouded her mind into a fugue state. She would've questioned if she was having an erotic dream if it weren't for Katoris grabbing her throat and squeezing her carotid arteries with her fingers. She could still breathe, but it was hard to imagine her situation as anything but powerless.
"Now, be a good girl, and tell me how much you want me to fuck your brains out."
Destiny barely managed to gulp as she gathered the thoughts she needed to massage Katoris's ego and hear those two words that, although innocuous, sent a delightful shiver down her spine. "P-please fuck me...!" she gasped out.
Katoris smiled, almost giving in to mirth. "I can tell you're trying your hardest to keep it together. You really love my cock, don't you? You were practically slobbering over it a couple minutes ago."
Destiny blushed when she heard such a vulgar accusation. She did it because she wanted to live. That much was true. But she had to admit that she took inspiration from what she saw the first time they met in Fiona's dorm room. But did that mean she enjoyed Katoris's prick that much?
With her body demanding tender loving care, Destiny conceded to the question. "I do...! I want it so badly right now!"
Katoris slowly let go of Destiny's throat. "There. That wasn't so hard to say, was it? You really are a **good girl~!**"
Destiny shuddered as she heard it again. "I am...?"
"Of course, my pet!" Katoris replied, moving back and grabbing hold of Destiny's thighs. "Now let Mistress take good care of you."
Katoris started slowly as she reared her hips back before pushing back in. She watched as the bulge along Destiny's abdomen retracted and extended, which made her thrall squirm and moan.
With every thrust, Destiny's body gradually changed. Breasts finally formed, which dispelled her body's androgynous appearance. Her breasts became bouncier as they developed in size. Each thrust also made Destiny's thighs thicker while her hips widened at the same rate that her ass fattened and became rounder. Her waist shrank as though a mysterious force pinched each side closer together. And, just as Katoris had told her, Destiny's fair skin slowly lost its pinkness in place of a shade of blue that gained more saturation.
Katoris licked her lips as she watched Destiny's breasts balloon to the point they were as big as her head. She could feel those thickening thighs squeeze tighter around her hips.
"Fuck...!" Destiny cried out, already on the edge of a climax but without the release that came immediately after. "I want to cum so bad!"
"Patience, dear~!" Katoris cooed. "We'll have our orgasms together. I'll make sure of that."
Katoris had her thrall wrapped around her finger. She could deliver incredible pleasure and intense pain with only a thought. Destiny's body was like wet clay, while Katoris was molding it into whatever shape she desired. This level of power was almost intoxicating to Katoris, but most of all, it turned her on to no end.
Katoris grabbed Destiny's legs and forced them back until her feet were next to her head, bringing her into a deep and intimate Folded Missionary position. With gravity now on Katoris's side, she used this opportunity to speed up her thrusts and intensify the power behind them. With her body enhanced by the pact she made with Destiny, she had an easier time maintaining what used to be a pace requiring her total effort.
Destiny couldn't even focus on how much her body was changing. She could see her breasts were getting bigger. She could feel her labia plumping up in an attempt to swallow more of Katoris's cock, while her fat balls slapped against her expanding bubble butt. She even saw her skin was now as blue as the sky. But her mental bandwidth kept her from acknowledging and processing the situation.
With Katoris taking control, the best Destiny could do was succumb to the intense pleasure that sheared through her body. But when a climax finally arrived, her's was overshadowed by the sheer volume of cum Katoris pumped into her. Although her newly enlarged tits kept her from seeing what was happening, she could still feel how effortlessly her womb filled up like a water balloon. Finally, all the new stimuli her mind was introduced to got the best of Destiny. Her eyes felt heavy, and soon after, consciousness eluded her.
When Katoris's orgasm ended, she looked down to see that Destiny had already fainted. She smirked and commented, "Mortal minds sure are fragile. Still, you turned out wonderful. You're going to be a wonderful succubus once you wake up."
As Katoris examined the sleeping bury she had her cock buried in, she realized what their size difference was now that Katoris's power had grown. She was a head taller now, so it was only fair that her pet got to be as well.
Katoris placed her hand on Destiny's sperm-filled belly. The latter's body briefly flashed red as her round belly rapidly shrank back down to a toned stomach. Immediately after this, Destiny's body lurched in both directions as her legs got longer while her head slid closer to the bedpost, almost knocking her head against it and waking her.
Satisfied, Katoris smiled. She then leaned forward, moving over those breasts that were too large to fit in standard bras, before giving Destiny a gentle kiss on the cheek.
"You and I are going to be inseparable," Katoris whispered, remaining fully penetrated inside of Destiny. "Because there is nothing in my world or this one that will keep us from being together."