Just a 'Test' (My Hero Academia)

Poll Winner

Themes: Threesome, Marathon Sex, Breeding

Summary: Based on this image. Mei has made quite a name for herself making support items from heroes throughout Japan, including Izuku and Nejire. Her latest invention could save lives and aid heroes worldwide, it only needs to be tested. A stamina enhancer made by a lunatic with no understanding of safety measures, what could go wrong? Nejire certainly isn't complaining though, so Izuku supposes he can't either.

-x-X-x-

“Are we sure this is… safe?”

“Nope!”

Izuku shoots a look at his favorite Support Hero. He loves Mei Hatsume to death, really he does. But there was simply no denying that the pink-haired inventor was… a little crazy.

“Mei…”

Grinning at him unrepentantly, Mei just giggles, not an ounce of shame in her voice.

“I wouldn’t need your help testing the damn thing if I was sure it was safe, Izuku! I would have already put it on the market! I need to make sure it’s safe for the average hero to use, and that’s where you come in Mister Number One!”

She raised a good point. Mei had made quite the name for herself making support items for heroes all throughout Japan and even the world beyond. She was the founder of Lightly Labs, which had become a widely renowned manufacturing company by this point. The secret to her success wasn’t just her public partnership with the Number One Pro Hero, yours truly, but also their private partnership.

Put simply, Izuku could handle things that other people couldn’t. And that meant he could handle Mei’s little mishaps better than most. If something hurt him, it would probably seriously injure or kill someone else, so Mei knew she had to go back to the drawing board.

Izuku didn’t mind being Mei’s guinea pig though. He used her (thoroughly vetted and official) support equipment in the field himself after all, so trying out the prototypes in a closed environment for her… well, that wasn’t really a hardship for him. Only, this time was different.

“I’ve already got a lot of stamina, Mei. I’m not sure if we want to give me MORE stamina and energy. Sounds like a recipe for disaster, to be honest.”

Mei’s latest invention was a belt that she claimed gave it’s wearer a ton more stamina and energy, basically allowing them to push beyond their natural human limits for as long as they were wearing it. And the craziest part was, it wasn’t based on adrenaline either.

Izuku didn’t pretend to understand the science behind it, even though he considered himself a pretty smart guy. But he did know that thanks to One for All, he was one of the most powerful people on the planet already. A stamina enhancer made by a (beloved) lunatic with no concept of safety concerns sounded like a bad idea when paired with his Quirk.

Giggling some more, Mei pats Izuku on his broad chest.

“Silly ‘Zuku! You’re not going to wear the belt! You’re going to put it and its wearer through their paces!”

Huh? Izuku blinks as the door opens and out steps a lightly blushing Nejire Hado. Izuku blushes a bit too because… well, the two of them kind of have a weird thing going on between them. They weren’t close back at UA, but they’ve been seeing one another more and more ever since they both became Pro Heroes.

Izuku hadn’t taken the Number One Pro Hero spot from Nejire, thankfully… but she was Number Two now, having reached it just one short year after he finally made it all the way to the top.

They saw each other at a lot of events, but disasters and parties, and they exchanged chit chat all the time. Izuku… kind of had a crush on Nejire if he was being honest, especially after no relationship emerged with any of the myriad number of girls he’d been crushing on back at UA. And sometimes, it felt like Nejire was flirting with him.

That said…

“Are you sure about this, Nejire?”

Blushing harder, Nejire nevertheless nods her head.

“Yes! I’m sure. Mei has explained everything to me… I’m ready to test the belt.”

Izuku hums, scratching the back of his head and glancing over at Mei.

“… I’m not sure if I’m the right person for the job here, Mei. I don’t know if I really want to fight Nejire, even in a friendly setting.”

What he really means to say is that he’s not sure he’ll be able to actually give it his all when it’s a woman he’s crushing on across from him. He might contaminate Mei’s data by not giving one hundred percent.

Mei just grins at him.

“No need to worry about that! You’re not going to be fighting Nejire anyways, Izuku. This is preliminary testing, after all!”

What? What did that mean, exactly? Izuku is about to ask what the hell Mei is talking about, when he suddenly glances over at Nejire and goes bug eyed at the sight of the beautiful Pro Hero stripping naked right then and there.

“W-Whoa!”

But Nejire doesn’t stop stripping, even as she smiles at him.

“Since we don’t know for sure how good the stamina belt is yet, Mei wants us to start out by having sex with it, Izuku. I hope that’s okay?”

Looking anywhere but Nejire’s naked body, Izuku swallows convulsively.

“I-Is it okay with you?!”

“… Of course, why wouldn’t it be?”

Seriously?! And yet… he couldn’t pass up an opportunity like this.

“Well, if it’s okay with you… then I guess it’s okay with me too…”

“Great! Let’s get started!”

Mei doesn’t bother hesitating once she has both of them on board. Izuku watches on in shock as Mei prepares a naked Nejire. The belt goes around Nejire’s waist, glowing green… and a pair of nodes go on her nipples. Finally, Mei puts a bit in Nejire’s mouth, forcing Izuku to speak up again.

“W-Whoa… is the gag really necessary?”

Mei gives him a look like he’s stupid.

“Yes? Don’t want her biting through her tongue or anything after all!”

That was… fair. Meeting Nejire’s eyes, Izuku swallows when he sees nothing but excitement and interest in her gaze. Well shit, he was in too deep to back out now, wasn’t he? The green on Nejire’s belt begins to glow as Mei turns on the experimental piece of support equipment. Nejire herself starts to spark a bit. Her Quirk literally allows her to convert her vitality and stamina into energy, so that’s not all that surprising. Still…

“Well? Get that dick out and get to work, Izuku! The belt isn’t getting tested if Nejire isn’t getting taken to her limits! I know you and that big fat cock of yours can do some serious damage, so don’t you dare hold back like you always do with me, got it?”

Izuku groans, covering his face with his palm as Mei just… throws out their friends-with-benefits relationship like that.

“Mei…”

And yet, when he glances at Nejire again, she doesn’t look upset or disgusted that he and Mei sleep together on the regular. If anything, she looks… intrigued? Or maybe he’s just imagining things.

Still, Izuku does as he’s told, pulling out his dick and stepping forward while giving the gagged blue-haired heroine a curious look.

“How do you want to do this, exactly?”

Nejire considers that for a moment before shrugging and making a strange gesture with her hands that Izuku doesn’t quite understand. When he stares at her blankly in response, she smirks around the bit in between her teeth and then gets on all fours. Alright then. Doggystyle it is.

Getting down on his knees behind her, Izuku grabs hold of Nejire’s full ass with both hands. He never thought he would be doing this with her. Even though he’s the Number One and she’s Number Two, it’s always felt like she’s been unapproachable in terms of relationships. Apparently, all Izuku had to do was get Mei to set up a test involving sex of all things, heh.

“Stop pussyfooting around, Izuku! Drill her, you big dicked bastard!”

He could do without the peanut gallery… but fuck it, this was what they were here for. With a growl, Izuku thrusts into Nejire from behind, shocked at how slick and wet her pussy was. Nevertheless, she’s very tight and it takes him a bit to push into her. Not too long though, because Nejire is quick to push back, thrusting her hips back in the direction of his throbbing mast.

Soon enough, the sound of flesh slapping against flesh fills the air as Nejire… surprises him with her ferocity. It’s not accurate to say she’s giving as good as she gets as he plows her from behind. Because instead, she’s giving BETTER. Quite quickly, Izuku has to pick up the pace and even start pulling on One for All a little bit in order to keep up with Nejire of all people!

“Heh, nice so far. Keep up the good work, you two!”

Over from where she’s monitoring the data coming in, Mei gives them a big thumbs up that Izuku automatically returns without thinking. Flushing, he quickly puts his hand back down and focuses on what’s happening… fucking Nejire Hado of all people silly.

Suddenly, in a burst of movement that leaves him speechless, Nejire pushes back so hard that Izuku falls on his ass. His hands never leave her hips though, so he winds up taking her with him. Sitting there with her in his lap, Izuku can barely keep up as Nejire begins to bounce while looking back over her shoulder at him with… loving eyes?

He’s probably just imagining things. It’s probably just lust. Though he can’t deny that she’s moaning through the bit in her mouth just as much as she’s drooling through it. Suddenly, Izuku understands those hand gestures Nejire was making earlier a lot better. She wasn’t suggesting just one position… she was suggesting they do as many positions as possible!

With that thought crystallizing, Izuku finally stops holding anything back. He finally lets loose for real and begins to go ham on the beautiful woman currently bouncing on his lap. His hands go to her tits and his mouth goes to her neck and he draws on One for All even more to have the energy and power to keep up with her.

Nejire moans wantonly through the ball gag, even as lewd squelching noises and all sorts of other lurid sounds continue to fill the air.

SLAP! SLAP! SLAP!

Finally, Izuku spins her around on his dick and stares her right in the eyes as she hooks her arms and legs around his body. He’s not expecting it to feel quite so intimate, but even if the gag makes it so he can’t kiss her, being able to look her in the eyes does make Izuku go even harder.

Until eventually, he pushes her onto her back and fucks her even harder. All the while, Nejire is still giving as good as she’s got. All the while, even as she orgasms around his cock, Nejire is moving her body and matching him the whole time. Izuku grunts but ultimately, there’s nothing he can do but knuckle down, is there?

In the end, they fuck for what feels like an eternity. Over and over again, position after position. Izuku cums and doesn’t even think twice about it. Then he cums again. And again. Nejire though… she climaxes easily half a dozen to a dozen times for every single release Izuku has. She squirts and she clenches and she milks him for all she’s worth.

By the time Izuku has cum five times inside of her, Nejire is still ready for more and even Izuku isn’t sure about how much longer he can go. He glances over at Mei to see her staring down at the data with a fascinated expression on her face.

“M-Mei… think you have enough yet?”

Before Mei can answer, Nejire clamps down on him again, squeezing him for dear life and making Izuku groan as he looks back to her. It’s clear she doesn’t want to let him go, even after all of this.

“Huh? Oh yeah, I guess you guys can stop now~”

Finally, before Nejire really can drain him dry with her insane stamina, the green glow of the belt turns off and fades away, leaving her to slump back as the energy immediately flees her. Izuku blinks as he pulls out of Nejire’s pussy… only to blanch at the sheer amount of semen that tries to evacuate her womb afterwards.

He hadn’t really thought twice about it in the moment, but holy shit he might just have knocked Nejire up! Meanwhile, Mei walks over and casually removes the belt along with the bit in Nejire’s mouth. As soon as she’s done, Izuku apologies profusely.

“N-Nejire, I’m sorry, I shouldn’t have cum inside…”

“Heh… d-don’t worry about it, Izuku. I wanted you to~”

What? Izuku blinks, even as Mei gives him an amused look.

“Sheesh, and people say I’m oblivious sometimes, Izuku. Did you really think I would set up a support equipment test involving sex without having an ulterior motive?”

Huh?

“Teehee! You’ve just been tricked into having lots of really enjoyable sex with the woman you’ve been crushing on for years… and who has been crushing on you right back all this time, you dense motherfucker!”

Izuku is almost ready to be angry in the first half… and then he catches up to the second half and his brain bluescreens for a moment as he sputters in shock.

“W-Wait… what?!”

Reaching up with a shaking set of exhausted fingers, Nejire places a hand on Izuku’s cheek, smiling tiredly.

“S-Sorry… I guess we were both really bad at telling one another our feelings for each other…”

Yeah. That was an understatement. Izuku blushes but when Nejire tries to lift her head only to fail, he leans down and gives her what she wants… a deep, loving kiss with lots of tongue. They makeout for a moment until Mei’s voice interrupts them.

“D’awww, you two are adorable~”

Lifting his head, Izuku gives Mei a very deliberate sort of look.

“… You’re in trouble, Mei.”

Mei jolts at that before looking suddenly nervous.

“H-Hey now! All I did was help!”

“In the most underhanded way possible, yes.”

“C’mon, Izuku!”

“Nope… someone deserves a spanking!”

Pulling out of Nejire and climbing to his feet, Izuku begins to chase Mei around the lab. Even after that marathon bout of sex, he could have caught her easily with some Quirk usage, but Izuku keeps to just his normal speed and strength as he chases the laughing, cackling inventor around her space.

In the end, he’s not truly angry with her, obviously. After all, all was well that ended well. But… if he catches her, he’s still going to tan her hide red for this!