The Wonky Potion (Konosuba)

The Wonky Potion (Konosuba)

A/N: The Wonky Potion was a commissioned one shot originally written back in August of 2020. Posting it up here and now for people to enjoy!

Summary: In which Kazuma buys a new stamina potion from Wiz's Shop, but it doesn't exactly work as he expects. Then Darkness imbibes the rest, and, well... things will never be the same between them, ever again.

Themes: Rough Sex, Bondage, Dom/Sub

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It was just supposed to be a new kind of stamina potion. At least, that's what he'd thought when he'd bought it from Wiz's shop. Arriving back home, Kazuma quickly uncaps the potion and takes a sip, figuring it'll help him get through his day if nothing else, and wanting to try it out. Immediately, he feels a little... different.

It's hard to place though. He certainly feels more invigorated then he was before. But at the same time, it's a strange sort of invigoration? Still, it was a NEW type of stamina potion, right? Obviously it wasn't going to feel like the old stamina potions. With a shrug, Kazuma decides to just go along with it, ignoring the feeling for the time being and just... getting ready to go about his day.

This proves to be something of a mistake when the door opens, and a familiar voice calls out.

"Kazuma? Where are you?"

Darkness, the masochistic blonde crusader, comes around the corner and Kazuma makes the mistake of looking up and beholding her body, clad in her usual armor, but nevertheless obviously exceptionally well-proportioned. Especially that... that ass. Staring for a long moment, his mouth open and just a bit of drool coming out, he stands there frozen just long enough for Darkness to furrow her brow and take a step towards him.

"Kazuma-?"

"Gotta clap those cheeks!"

The sudden exclamation from the delirious, horny young man is followed up by him launching himself forward. In response to the sudden, seemingly unprovoked assault, Darkness flinches back, covering her face with her arms in a cross, thinking that he's about to attack her. Of course, this leaves her utterly defenseless to his real goal, allowing him to slide right around the reeling crusader and...

SMACK!

With a gusto that even Kazuma himself can't begin to understand, and a wide grin on his face stretching from ear to ear, he lands a HEFTY slap across Darkness' derriere, landing the mighty spanking across her unprotected, unarmored ass cheeks. For just a moment, the room is filled with nothing but the sound of that resounding clap of hand against buttocks, and Kazuma's eyes are fixated on Darkness' jiggling behind.

But then time catches up, or maybe more accurately Darkness catches up with what just happened to her, squealing in both pain and arousal as the masochistic crusader shudders a little. Bringing her arms down, she tries to whip around and demand an explanation, but to her shock and surprise, Kazuma is just plain... quicker right now.

In a split second, the Crusader has been disarmored. Kazuma's hands move so fast that Darkness doesn't even have time to react before he's somehow untied and unclasped and undone her armor, causing it to all fall to the ground with a clatter around her. All she's left with is her form-fitting body-stocking, and even as Darkness blushes and stutters and stammers, Kazuma is getting up close and personal... and grabbing her ass again.

"K-Kazuma!"

She finally gets his name out, but he really pays her no mind. He does speak, but his attention and thus his words are focused entirely on her behind as he grips and gropes it, as he smacks it and runs his fingers across it.

"Mm, your ass has quite the luscious bounce, Darkness. Even though it's firm from all your training, even with your fitness, you have a woman's behind... feminine in all its fullness and jiggle."

Darkness' eyes widen at the crass compliments. This is very much unlike the Kazuma she knows... but also not at all unwanted, truth be told. She's beside herself in arousal and confusion, even as Kazuma slides his hands from her ass, up and around to her breasts. Darkness lets out an 'eep!' but doesn't actually stop him as he hefts her breasts in each palm, clearly appraising and judging them.

This involves juggling them to test their weight and their bounce, as he casually explains to her. And then his fingers are pinching one of her nipples between them and pulling it, and Darkness is squeaking and squealing in pleasure as he just so... easily plays with her body. This is NOT the Kazuma she's used to... b-but is that a bad thing?

His hands move across the rest of her body, even clad in her stocking as she still is, and Darkness does her best (not really) to resist.

"K-Kazuma, I don't know what's come over you!"

She blushes as he just gives her a cocky grin and smacks her ass again, almost off-handedly.

"Kazuma! You... I-I won't submit to your v-vile urges!"

Snorting derisively (because despite her words, she really isn't fighting back as hard as she could) Kazuma goes ahead and presses their bodies together, more importantly pressing their crotches together. Darkness gasps and looks down, her jaw dropping at what she sees. Kazuma has quite the impressive hard-on if that bulge is any indication, and he's pressing it right up against her pussy. Only his clothing and her thin black body stocking stands between their privates.CHeCk for new stories on no/v/el/bin(.)c0m

The realization has Darkness trembling, and the way Kazuma proceeds to grind against her, dry-humping her right then and there, has her trembling even more. When he begins to talk, however, it becomes harder and harder to keep her thoughts from straying down... debauched paths. Especially as Kazuma talks in a low tone about what he's going to do to her.

"... I'm gonna fuck you now, Darkness. You slutty, horny, masochistic pig of a Crusader. Ima claim your fat ass, and the rest of your body as well. I'm going to make sure that you're ruined for other men. When I'm done with you, you'll wait on me, like a servant or a pet, eager to blow me or accept my dick into your ass or cunt."

By the time he's done monologuing, Darkness is moving in time with Kazuma's humping, her exposed face and hidden body both aflame as she pants heavily. She knew she should be stopping this... she knew that something wasn't right, that this couldn't really be Kazuma. She also knew how easy it would be to overpower him if she actually tried. She was a Crusader after all, and her strength, stamina, and durability could not be matched easily.

But the grinding... the hint of things to come... t-the debauchery! She was so close to having everything she'd ever wanted, she was-

The moment ends when the front door opens and Kazuma easily slips away. After all, it'd been him holding onto her while she trembled in his grasp, rather than her holding onto him. Darkness makes a single aborted attempt to reach for him, but he's still so damn fast. In the end, Darkness is left alone in the foyer, so close to release and so thoroughly denied.

Frankly, she wasn't sure if she would climax on the spot from such underhanded tactics, or if she would crush Kazuma's head for teasing her so effectively. But with the arrival of Megumin and Aqua, there was nothing the Crusader could do but gather up her armor and pretend like nothing had happened. She did spend the rest of the day glaring at Kazuma while they went on quests, however. W-When she wasn't blushing and sneaking peeks at him and imagining the two of them doing that again, that is...

-x-X-x-

Kazuma... Kazuma was freaking out, just a little bit. Needless to say, the small sip of potion he'd taken had worn off just in time, coinciding perfectly with Megumin and Aqua's arrival. Though, he supposed 'perfect' would be having never taken the sip in the first place or done... a-all of that to Darkness. Shit, he was in big trouble, wasn't he?

The look on Kazuma's face stops her dead in her tracks as he grins viciously and slaps his messy, fat cock down between her breasts, using her tits to rub against the sides of his member as he thrusts back and forth. His hand curls in her long hair, and he sneers down at her.

"This what you want, you little bitch? For me to ruin you? For me to make a mess of you? I should parade you through the city streets after we're done her. Let everyone in town see what sort of lewd cunt you really are, you pig slut! Fuck!"

He's thrusting forward harder now, and Darkness is of two minds. She really should tell him that the potion has worn off... but at the same time, she's immensely aroused by the words he's saying, and by the very idea that Kazuma is finally dominating her. It's a conundrum to be sure, and Darkness is quite torn. In the end though, her opportunity to speak is taken from her, the choice snatched away when Kazuma pushes his cock forward from her breasts into her mouth, yanking on her blonde hair to lift her head up so he can fit his dick past her lips.

"Suck it, bitch! Suck my fucking cock!"

Moaning rather wantonly in humiliation and the arousal that she's feeling because of that humiliation and embarrassment, Darkness does as she's told and sucks Kazuma's 'fucking cock' as diligently as she can. Of course, with how he's going, it's more like she's enduring him fucking her face rather than actually doing that much to help him get off. Kazuma is in complete control... which given that's what she's always wanted, is so much of a turn on for Darkness that she's cumming just from being forced to deep-throat his cock, her lower body shaking and spasming in bondage as she squirts her pussy juices all over the bed.

"Gagkh! Gagkh! Gagkh!"

"Yeah! Yeah, that's right, ain't got nothing pithy to say now, do you bitch! Fuck, fuck, FUUUUUCK!"

With that last shout, Kazuma begins to cum, even as Darkness notes in the back of her mind that it's him who's gotten noisy now. If he expects the rest of the household to not know anything about what they've been doing for however long it's been now since they started going at it, Kazuma has another thing coming, that's for sure.

Most of Darkness' attention is on the cum being deposited in her mouth though. He pulls back before truly beginning to cum, so it all collects on her tongue, and when Kazuma finally pulls out from between her lips with a pop entirely, Darkness makes a big show of lolling out her tongue for him, showing him all of his collected cum before she takes it back into her mouth and swallows hard.

Potion be damned, Darkness doesn't give a fuck about that anymore. Maybe that potion was what had gotten them to this point, but in that case, she was just plain grateful. And no matter what, she refused to let this opportunity slip her by. That's why, even though she can't plead that it's the potion making her act this way any longer, Darkness licks her lips and looks up at Kazuma pleadingly, needily, desperate in her desire.

"Are you... are you going to humiliate me more with your wicked penis, Kazuma?"

If Kazuma notices that Darkness has changed from challenging his manhood to debasing herself and calling him wicked again, he doesn't make mention of it. Instead, he slaps her across the face a couple of times with his saliva-coated cock and grins down at her.

"Call me Master or sir, bitch!"

"Y-Yes sir!"

Sliding back down her body, Kazuma uses the bind skill again, reworking things so that Darkness' ankles and wrists are suddenly tied up, her body folded into a pretzel, contorted rather uncomfortably. But at the same time, that discomfort feels good, and Darkness moans as she's put on her back and fucked in a mating press. Kazuma thrusts forward into her defenseless twat without a care in the world. He's already cum inside and on her so much, and he just keeps going, snarling down at her, dominating her.

That potion had awoken something within Kazuma, Darkness realized. Even as she climaxes again and again, even as she squeals at the top of her lungs, she recognizes that they can never go back to the way things were before after this.

"A-Ah! I'm being defiled! My purity, it's been claimed by Master! Fuck me harder, sir! D-Don't stop, I'm just a slutty crusader who deserves to be punished by your wicked member! F-Fuck!"

Kazuma doesn't bother silencing her as she cries out, as she extolls the sins of her new Master, as she slowly breaks before him and submits like she's always secretly longed to do. He merely grabs onto her tits, casts another drain touch for good measure, and keeps on fucking her, fully intending to make good on all the promises he made while under the influence of that damnable potion.

With a triumphant roar, he unleashes another load inside of Darkness' messy twat... but it's far from the last. The night is still young, after all, and Darkness is still ready to go, eager to be fucked silly one creampie and drain touch at a time.

-x-X-x-

Waking up the next morning is... hard, to say the least. Kazuma lets out an extremely soft groan as he feels himself coming back to consciousness. Not even wanting to open his eyes at first, he doesn't, instead shifting this way and that and trying to take stock of what was going on. He's never been more exhausted, he's pretty sure.

He feels like he didn't get a wink of sleep, to be honest. What... what did he even do last night? Why was he so fucking sore all over? And why did his hips feel weird? Slowly, Kazuma opens his eyes and stares up at the ceiling blearily, blinking a few times. Then, he turns his head and sees Darkness' sleeping face beside him, peaceful and almost cute, if not for the cum coating her face to go along with the drool coming out of her mouth.

Huh, that's interesting. At first, Kazuma closes his eyes and tries to go back to sleep. He really is tired, and he needs a lot more rest if he's ever going to recover from whatever the fuck happened to him. Of course, when he finally realizes just what it was he'd just seen, when the image of Darkness asleep and coated in cum laying next to him finally processes in his foggy, beleaguered brain...

"What the fuck!"

Shooting up from the adrenaline suddenly coursing through him, Kazuma throws back the sticky covers and stares at Darkness in all her nude, well-fucked glory. The bed... the bed is a mess, probably unrecoverable to be honest, but Darkness, despite being just as messy... looks fucking good. Getting fucked into a pleasure coma agrees with the blonde Crusader, and even now that he finally remembers exactly why he's so tired and so sore, Kazuma finds himself getting hard again, just a little, looking down at Darkness.

He's shocked, but he's also kind of proud. He'd done it, hadn't he? He'd fucked Darkness into a stupor through liberal use of drain touch to keep himself going while slowly tuckering her out. Heh, it was one way to defeat the blonde Crusader in a physical contest, Kazuma supposed...

Still, he also remembered how many times he came inside of her now as well, and that makes his cock wilt a little as he grimaces at the thought of knocking Darkness up. He really wasn't ready to be a father or raise a child...

As these feelings war within him, pride fighting panic for supremacy, a sudden knock at the door startles Kazuma from his thoughts. Oh shit... his door was locked, thank fuck, but he still had a cum-coated well-fucked Darkness sleeping in bed beside him.

... This wasn't going to end well for him, was it?

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