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He had originally wanted to be a hero; someone who came in at the last moment and saved the day. He wanted to be someone who was loved and adored by the public, but when he finally acquired the strength to make that dream a reality, it was too late; the public already feared and hated him.
Saitama didn’t really like being called a ‘bad guy”. It always made him think of the Sentai Warriors shows he watched as a kid, with cheesy action scenes and the simple “good triumphs over evil” plot lines. The bad guys always lost. They were dumb and weak.
He kind of liked the term “villain” mostly because it had an air of sophistication about it. Villains weren’t dumb, nor were they weak. The only thing he didn’t really like about them was that they were expected to be underhanded and they cheated. He didn’t really do those kinds of things.
It’s not like he went to the supermarket expecting to be given free groceries. It wasn’t really stealing when they gave them to him just to get him to leave. And he really didn’t need to do much to take out the heroes that challenged him. You would think that someone labeled as an S-Rank hero would be able to take a rock to the head without dying. How was he supposed to know otherwise?!
He had gone on for a while, living as a “villain”. He fought monsters and he fought heroes. It always ended the same: too quick, too messy, and just so... boring . It had reached a point where he didn’t really feel like his fights were worth the effort and money to clean himself and the dirtied clothes.
He didn’t care how it happened, he just wanted to do something fun.
Saitama just never would have guessed that “fun” came the form of a small, sassy cyborg monster.
It was by total accident that they met in the first place. Saitama was on a midday stroll, hoping a decent hero or monster would show up and give him some kind of challenge, but what he found was far more interesting: some weird bug-girl monster lying on the ground, screaming bloody murder. All of her limbs, including her wings, were driven through with large metal poles, pinning her in place.
There didn’t seem to be anyone else around so Saitama approached her to get a better look, but just as soon as he was within reach, he suddenly sensed something coming towards them from above at a high speed. He jumped back a bit out of reflex, watching as another long, metal pole drove itself down into the center of the girl’s chest. She made a sick, gurgling groan before blood gushed from her mouth and she fell still.
Saitama couldn’t help but look around the tops of the buildings to try and figure out where the pole had come from.
“Hah! You ugly bug-bitch! Bet you’re regretting starting shit with me! What’s this? Not so chatty now, I see.” The voice was close and echoed through the abandoned buildings.
“I’m pretty sure she’s dead, so she won’t be answering you.”
“What?!”
Saitama watched a small figure jump down from the building directly above him and land a few feet away. This guy really was small… and shirtless; showing off a very human torso that connected to metal arms, but, of course, with those spiky shoulders and the blade-like spines coming off his elbows, it was probably pretty difficult for him to wear shirts in the first place.
“Piece of shit. She couldn’t even last long enough to be any real fun.” The mohawked redhead poked the side of her face and that’s when Saitama realized he was also… barefoot? But then again he didn’t really have feet as his non-human legs just tapered down into sharp needles. How was he keeping his balance?
“Oi! Eyes up here, baldy!” His hands were far too large for his size and his arms were far too long - one long, clawed finger low at his thigh, directing his eyes upward.
Then he registered the “bald” remark.
“Who are you calling “bald,” you little brat?”
“Uh… You. The only one here who has no hair.” Oh, the look on his face was enough to really piss Saitama off. He was standing with both of those large hands on his hips, sneering; arching a perfectly lined eyebrow and showing off his white, sharp teeth.
“Say it one more time and I’m going to punch you in your pretty-boy face.” Saitama stalked forward, towering over the little imp.
“Mmmh? You want me to say it again?” He moved quickly, wrapping his large hands around the back of Saitama’s neck and driving his needle - feet? - into the denim as he climbed the larger man until they were face to face. There was a look of obvious surprise in the kid’s expression when he realized Saitama was not only supporting his weight unflinchingly, but was completely unharmed from being stabbed.
“Oi, don’t climb people like they're trees. It’s rude.”
The boy’s eyes were eerie with the black slitted pupils surrounded by full crimson as he squinted; studying him.
“Hmph… You seem stronger than you look. What’s your name?”
“It’s Saitama.”
“Oh! Well, in that case, Saitama,” the kid kicked of Saitama’s thighs and landed a very thick, supple ass on his shoulder. Not that Saitama was focusing on his ass. Dudes didn’t do it for him. “From now on, you can be my slave.”
“What?! Look here, you little shit! If you keep pissing me off, I really will punch you!” Saitama made to grab the kid and toss him off, but one large metal hand grabbed his and placed it on his thigh instead. Saitama could feel his face heat up and he snatched his hand away.
The kid laughed and patted him on his head. “Haha. Don’t worry, Saitama, I’m a good master. By the way, you can call me Genos.”
Saitama was quiet for a moment. On one hand, he could punch this kid - Genos - and be done with him. Or he could let this play out and see what comes of it. It’s not like the brat could ever make him do something he really didn’t want to do.
“Yeah, ok. I guess we can play for a while, Genos.”
“That’s the spirit! We’ll make a decent monster out of you, for sure!”
“Who said anything about me wanting to be a monster?”
“You are Saitama the Human Monster, are you not?”
“Is that what they’ve been calling me recently?”
Genos made a sound of affirmation and crossed his legs, casually leaning against Saitama’s head as he braced himself with his hand on the other shoulder. The kid’s skin was really smooth and warm - but it wasn’t like he was paying that much attention to something like that.
“I’m surprised to see you’re still human for the most part. Humans and monsters alike talk as if you’ve got thick armored skin that’s impenetrable and a wicked glare that can paralyze your enemies.”
Saitama couldn’t help but chuckle at the image that conjured. “Well, I have yet to find something that can pierce my skin, but I don’t know about a paralyzing glare.”
“Well, we’ll see what kind of abilities you gain after a proper transformation. You’re still too repressed. Once we get you to open up, I’m sure we’ll learn all sorts of fun things about you.”
“Yeah, whatever. What am I supposed to do with you anyway?”
“Take me home with you. Duh. Wait, you do have a home right? Like a place with power and running water?”
“Yeah”
“Good. I want a real bath! Ooh! And if you carry me the whole way, I’ll let you wash my back.”
“How gracious of you…”
-----
The older man never really thought he would be able to enjoy something like torture, but Genos was good at what he did and damn if Saitama didn’t loathe to admit, the brat looked good doing it.
Genos wasn’t the manic, loud, hysterical-laughter type when it came to having fun. He was very methodical, but in a soft, sensual way; he whispered delicious promises as he cracked bones and crooned lovingly as he tore at flesh. He always strived for 100% destruction of their minds as well as their bodies.
Watching him, Saitama could easily understand why some considered it an art.
True to his word, Genos always took the time to teach Saitama the best ways to elicit the most satisfying sounds and how to completely shatter a toy’s sanity.
The one time it really mattered was when they were playing with another one of Genus’ experiments. The doctor could be a real pain in the ass, but he was definitely creative and his experiments could often bring a bit a fun to an otherwise dull afternoon and this particular experiment was far more entertaining than they had originally thought. Genus had said he was immortal and they were free to test that fact as much as they wished within the given time limit.
Genos took the opportunity to give an extensive lesson.
~~~~ Torture Talk Starts Here ~~~~
“Come, Saitama, I want you to see this before it heals itself.”
Saitama stepped close, looming over the smaller creature as he surveyed the fresh cut across the throat. Genos grabbed his hand and pressed his fingers into wound causing the experiment's body to tense and a weak moan to pass the man’s lips as the only form of protest since he was tied up this time; his arms pulled tight behind his back in as wrist-lock and his legs uncomfortably wide by the spreader bar between his thighs.
“Can you feel how shallow I’ve made the cut? This is the best depth to cause a lot of pain, get a good flow of blood going, but should leave the toy alive for at least another half hour or so without killing it or sending it into shock.” Even in “teaching mode”, the boy whispered and caressed everything he touched, leaving long streaks of blood along the experiment’s neck and Saitama’s wrist.
The wound was already starting to close, but Saitama left his fingers there, letting the flesh close completely around them before tearing it apart again with a gentle flex of muscle. Most of the other wounds had already repaired themselves as well so the pain his actions caused was undoubtedly raw as the red-eyed man groaned loudly.
Genos hummed his approval as he moved to stand behind the experiment’s kneeling body, rending the flesh of the immortal’s naked torso with the sharp ends of his overly large hands as he leaned in to whisper filthy words of encouragement that would not be out of place in a porno; all the while keeping direct eye contact with Saitama.
The bald villain was not too surprised when he felt his cock react to the brat’s stare as it wasn’t too unusual for either (or more often than not, both) of them to get aroused when they played around like this. More than he’d like to admit, Saitama often found himself watching Genos more than their toys. The moans and cries of pain with the hard tang of copper in the air only serving as ambiance to the visions of the boy’s pale skin streaked in red or the tight stretch of fabric across that pert ass as he drove a pointed limb through pliant sinew.
~~~~ Torture Talk Ends Here~~~~
They continued their game well into the night. Saitama had lost track of the number of times they had killed the immortal, but each time was always the same: the largest part of him regenerating fully to an immaculate version of himself, leaving behind the gore of any previous bodies.
By the time Genus had asked for his experiment to be returned, Saitama was so hard, a stiff breeze could make him cum.
Throughout entire way home, Saitama was too conscious of everywhere he and Genos touched as the young cyborg-monster rode on his shoulder, his body warm and plush on the parts of him that were still organic. The smell of him was also truly distracting; the heavy stench of blood mixed well with his natural scent and the high end body wash he insisted on using. By the time they stepped into the apartment, the older man had already envisioned several different scenarios in extremely graphic detail as to how he would take the firey red-head; most of them required force, but he was prepared if it came to that.
Saitama could barely contain himself when he started to help Genos out of his pants to replace his legs; detaching one after the other from the integrated housings halfway up those pale thighs and setting them to the side. At the last minute, he decided not to reach for the house legs, watching as those short stumps spread themselves; intentionally provocative - he could clearly see the outline of the brat’s half hard cock as the thin material of his boy shorts stretched with the movement - so instead of finishing their normal routine, he hauled the cyborg up by his asscheeks and tossed him over his shoulder like a sack of rice. Genos made a slightly undignified sound, but that was it.
He didn’t question it when Saitama dropped him unceremoniously on the futon.
He didn’t protest when the older man turned him over and snatched away his underwear.
And he didn’t try to escape while the villain undressed.
Saitama was only slightly confused by his utter lack of resistance. He had expected Genos to struggle and spit venomous words at him at least a little bit. “Are you just resigned to let this happen, or do you actually want this?”
Genos glanced at him over the spikes on his shoulders and the little shit was smirking. “I’m pretty sure this is the last piece of your puzzle. I’m more interested in your transformation than unsuccessfully trying to protect my anal virginity. Do your worst.”
Saitama would be lying if he said that invitation didn’t kick his arousal up to an entirely new level. He really wanted to break this kid. Break everything from his body to that snarky little attitude, but he knew that if he did that, the fun would be over so he knelt behind his companion and grabbed a handful of the pert ass in front of him, instead; spreading the brat with his thumb to expose a pretty, pink hole.
“Hnn... Virgin is a nice color on you. Too bad it won’t be there for long...” Using his other hand, Saitama brought his fingers, first to his mouth, wetting them a bit, then pressed one into the tight, resisting heat. “You’re still human here, right? If we don’t stretch it out a bit, it’ll tear.”
“Mmmnh. I haven’t been human for a couple years now so even if it did tear, I’d heal just fine. If you’re too nice about it, I don’t think you’ll change. You need to give into your desires so I want you to fuck me up.”
“Just with doing this I’m already giving in! And I plan to indulge myself whenever I can from here on out. It really won’t be any fun if you’re not screaming for more so don’t try to pretend like you know what I desire!” Just for the hell of it, Saitama landed a firm smack to the cyborg’s ass and the sound Genos made shot straight through the older man’s body like an electric shock. He couldn’t hold back the growl of pleasure as he surveyed the bright red hand print that started to form.
“Damn, if you keep making noises like that, I really will fuck you up… Mmh, you know, like this, you look like one of those expensive fuck toys… I guess it wouldn’t be too bad to treat you like one, if that’s what you really want.” He added a second finger that was mostly dry and Genos let out a stuttering hiss, but rocked back all the same. The brat’s hole was clenching around the intrusion; squeezing tight and sucking his fingers in deeper so he upped the pace a bit, adding a twist to his thrusting. He wanted the kid wide open before he let loose.
After watching his fingers dig in a few more times, Saitama gathered a copious amount of spit from his mouth into his free hand and worked it onto his dick. In one swift movement, he withdrew his fingers and thrust his hips forward, pushing through the angry, red rim until the tip of his cock met a second boundary of resistance. He didn’t care that he was only about third of the way in; his mind was purely focused on the crushing heat surrounding him.
It was so good - so tight! - and he wanted to just fuck that perfect hole into oblivion, but instead, he withdrew a little then pressed forward again, this time pressing a little deeper. Genos gave the cutest wail and his walls gripped Saitama’s cock tighter, trying to prevent him from moving.
“C’mon now, if you keep squeezing so tightly, I won’t last much longer. I want to go balls deep at least once before I cum.”
“I don’t really have much control over it! If you want to fuck me deep then just do it already! I told you before, I want you to wreck me!”
A shudder ran through Saitama’s body and a tingle started at the base his spine, spreading all the way down to his fingers and toes. The boy was already began groaning and panting loudly from the involuntary flexing of his dick as those words stoked the fire of his arousal, so he gripped the cheeky brat’s hip with one hand and leaned over the small, lithe body below him; bracing his other hand just in front of the cyborg as he brought his face close to that pointed ear to whisper lewdly.
“Fine, I wreck your tight little ass-pussy, but you better not cry about it later.” And with that, he pulled those tiny hips back to meet his rough thrust and didn’t even pause at the raw scream it pushed from the young monster’s throat.
It took three good tries before Genos’ hips met his properly and once his balls met the brat’s, there was no stopping him. The quick and brutal pounding he started not only dictated the boy’s breathing patterns, but shook the belongings within the tiny apartment. The TV rattled loudly as it shifted forward on the stand and manga fell from the bookshelf in tandem with every thrust, but Saitama didn’t give a shit. He was too engrossed in the way his dick was practically melting in the embrace of the soft, pliant heat of the brat’s ass.
With every withdrawal, Saitama almost pulled out, leaving only the tip and there was barely a second that passed before he was thrusting forward again. It was frenzied and undoubtedly painful for Genos given the screams he was letting out and the way he clawed at Saitama’s arm, but the older man wouldn’t stop - couldn’t - he was too close. Their earlier game of seduction over the young experiment playing back in his mind vividly; the combination of that and the delicious sounds spilling from the tiny body beneath him pushing him closer and closer to the edge.
When he started to feel his balls pulling in and that tight gathering in his gut, he went all out; rearing up to put both hands on the boy’s hips and fucked him hard with abandon. He could only think about finishing, paying no heed to the way the boy’s sobbing wails cut short with every reentry. He wanted nothing more than to be as deep as physically possible when he finally came so he pulled Genos to him to meet every forceful thrust until finally - like a dam bursting to give way to a flash flood - his orgasm washed over him and he emptied everything he had into small cyborg-monster.
He was aware that he was drooling by the end of it; he could feel it gathered in his mouth and running down his chin, but when it dripped down, onto the swell of Genos’ ass, Saitama saw that it wasn’t drool, but blood. Swallowing what was in his mouth, he ran his tongue inside to find the wound and found his canines longer than normal and they dug into the gums of his bottom jaw uncomfortably when he grit his teeth.
“Well…. there wasn’t much of a change…… but I think it suits you well enough.” Genos was out of breath and his voice sounded strained and raw. It was probably painful for him to speak. His crimson eyes were teary and his face was a splotchy mess of red with his nose running and his lips bloody and swollen; a line of tiny indentations all along the underside budding with small red droplets. To Saitama, it was the most gorgeous thing he’d ever seen.
“Right now, I’m more interested in looking at you.”
“Yeah well, look all you want, just let me go. My ass is killing me.”
Saitama was still hard and had every intention of going again, so without pulling out, he turned Genos over - despite the brat’s protests - so the boy was looking up at him. In this position, the older man - monster, now - was clearly aware of his companion’s unsatisfied cock; heavy and leaking against the slim, pale stomach.
“I don’t think so. You clearly enjoyed that and I said it earlier: I’m going to indulge myself as much as I can. I’m gonna fuck you til I can’t get it up anymore and then, after that, I’m gonna eat your ass til you pass out.”
“Fuck me…. I’ve created a monster.” Genos groaned and covered his face with both of his over-sized hands, but his happily twitching cock easily gave away his true feelings about the situation.