Setsuna’s Size Struggle

(Note: This story is part of an ongoing series of My Hero Academia stories)
Previous Story (Part XXVI): [LINK]
Beginning (Part I): [LINK]
Next Story (Part XXVIII): [LINK]

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“Setsuna, are you alright?” Momo asked as she looked at the goofy expression on the girl’s face while rubbing at the huge distention in her abdomen. The two of them were in what was called a ‘Green Room’, though the only green thing in the room right at this very moment was Setsuna’s hair. In front of them was a large plasma screen TV mounted on one wall currently showing the studio for the talk show the green room was meant for. Izuku was doing pretty well with his interview so far, though the bulge in his pants was still somewhat noticeable.

 

“Haaah, I… I’m good! I can do thiiiis, heeeeee, it’s spreading me so wide, it’s getting harder and harder to think straight!” Setsuna said as she began panting softly, a trickle of drool running down her chin. “Say Yaomomo, think I can borrow your boyfriend some more after this…? Like say, once or twiiiice a weeeEEEEK!?” she squealed as the distention in her belly twitched then went to grab her own breasts causing her to whimper in pleasure.

 

Momo giggled, “Sure! I don’t think he’ll mind either!”

 

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It all began several hours ago at the Busteez Hero Agency. Momo, Izuku, and Setsuna were going to visit Melissa, who was now working at the agency. It seemed Midnight had given Melissa a room on the second floor like she had given Mei Hatsume. A place for her to tinker with her inventions that were meant for use in Busteez, or directly for the heroines who worked there. Since Setsuna was an employee as well, that counted. Momo walked next to Izuku with Setsuna on the other side of him. It seemed Setsuna had put in an order for a quickband a while back and thanks to her private lab room, Melissa finally had it ready. The dark green haired girl was on her way to pick it up when she ran into Izuku and Momo in the lobby. Momo then asked Izuku to drop by the agency so she could discuss something with him. Since he regularly used a quickband himself, Setsuna was hoping he could show her how to use one since she was worried Melissa would get really technical about it. Something about the blonde having explained some kind of contact control to her, only for Setsuna to learn through trial and error in the end.

 

They passed what looked like a large gym room where a bunch of exercise equipment had been set up, but nothing had been used yet. Momo could tell because everything was still covered with plastic sheets.

 

The moment they passed the gym though, a door next to it burst open, spitting out Mei Hatsume. The pink haired girl looked completely haggard, with deep dark bags under her yellow crosshair eyes. It looked as though she hadn’t showered in a couple days as well, though for Hatsume, that was actually pretty normal. The girl was always working on something or other. She would get so caught up in her work that she would begin to forget to eat and sleep. Momo suspected Midnight might have given her her own place inside the agency just so she could keep an eye on the girl.

 

“PERFECT! COME RIGHT THIS WAY!!!” she said excitedly as she grabbed Izuku and yanked him into her room slamming the door shut behind her. Izuku didn’t even have time to ask what for or even yelp in surprise. Thankfully, Hatsume hadn’t locked her door and the two other girls were easily able to follow her back inside.

 

“Waaah, Ha… Hatsume-san, what’s going on!?” Izuku said as Hatsume pushed a glass filled with an innocuous blue liquid.

 

“Hmmm, I think I just perfected the mixture for my Blue Baby #9! It’s a male and female performance amplifier that I’m hoping to use here at the agency to allow the fun to go all night long!” Hatsume said excitedly.

 

“Hang on, like a Quirk boosting drug?” Setsuna asked, her eyes narrowing.

 

“No no, a sexual boosting one!” Hatsume said. “I’ve already had some success with the pink variant I made to be absorbed through the skin, I use it in that.” she explained, jerking her thumb over to a heavily modified barbers chair with a bunch of mechanical arms bolted onto it. It honestly looked like some kind of torture device, but Momo knew it to be harmless. Mostly.

 

“Midnight asked me to make something like this for the older heroes that come in. A little pick-me-up to help them enjoy their stay a bit longer!” Hatsume continued to explain. She then pushed the glass to Izuku’s lips, pouring it into his mouth.

 

“Izuku!?” Momo and Setsuna said together when they saw him swallowing out of reflex.

 

Izuku blinked his dark green eyes, “Huh, it tastes like cotton candy soda…?”

 

Momo and Setsuna both blinked. Both girls expected the stuff to taste so toxic that he’d spit it out immediately.

 

“Well yeah! I wouldn’t want it to taste bad, about 99% of that was just sugar to help it go down easily.” Mei said, “Less than 1% was the actual chemical, though I’m pretty sure it was completely flavorless in its pure state.” she explained as she set the glass down next to an identical one filled with a lighter blue fluid. She then blinked her eyes, “Hang on, was it this one or…” she trailed off, “Whoops!” she said just as Izuku’s cock ripped straight out of his pants, shooting to a full erection in less than the blink of an eye!

 

“Izuku!” Momo and Setsuna yelled together as the green haired youth fell back into the modified barber chair, his cock throbbing in the air, thick veins pulsating along the shaft.

 

“Wow, more effective than I thought it’d be!” Mei said.

 

“Mei, this is serious!” said Momo.

 

“Is he gonna be okay!?” asked Setsuna.

 

“Hmm, yeah, it should be fine, not like it’s gonna explode or anything.” Mei said after she walked over to Izuku and ran her hands along his shaft, “Hmmmmm,” she said again before knocking her knuckles against the side, “Yep, that’s really solid!”

 

“Thanks Capt. Obvious! But is Izuku really gonna be alright, how long will this stuff last?” Setsuna asked.

 

Mei blinked, rubbing her chin with her hand while she thought, “Hmmmmmn… Three, four days tops.”

 

“FOUR DAYS!?!?” the three of them said together.

 

“At most, likely three, two if I didn’t get the mix right. But there won’t be any damage!” Mei said excitedly.

 

“But I… I have an interview…” Izuku said, “They’re going to be upset if I postpone it again.”

 

“Isn’t there an antidote or something?” asked Momo.

 

Mei thought for a moment before moving over to the controls for the chair, “Well, there IS one treatment.” she said while tapping away at the controls. The mechanical arms began shifting and moving around, and Momo gulped when one of them extended out a long needle. “I could drain the blood from your penis before giving you a massive dose of anti-inflammatories.”

 

“Wha-wha-whaaAAAT!? IS THAT A NEEDLE OR AN ICE PICK!?” Izuku said, panic clearly in his voice at the size of the six inch long stiletto of metal.

 

Momo and Setsuna both moved to flank Izuku’s cock as they spoke together, “NO WAY!” they said, both of them crossing their forearms together in a pair of X.

 

“Well, they might have a smaller one at the hospital…” Mei said, and Momo was a little worried at how disappointed the pink haired girl sounded.

 

“I have a better idea!” said Setsuna.

 

---

 

Setsuna’s idea, as it turned out, was to use her Quirk to separate her vagina from her main body and have Izuku use it to hide his erection inside! It was actually pretty fascinating to watch. Setsuna simply removed part of her crotch and slid it around Izuku’s dick like some kind of living onnahole! When his huge dick was pushed inside, instead of stretching out the black back end of her pussy where it had detached, it simply vanished as Setsuna’s stomach stretched upwards.

 

Setsuna explained it as her body wasn’t actually detaching so much as creating self contained portals that allowed her to be in two places at once. Or several, depending on how many pieces she split herself up into.

 

“HEEEEEEEEGEH…!” Setsuna whimpered, gritting her teeth together as she bucked her hips, “NNNNNGH, AHHH, I WISH HE’D MOVE AROUNNNND…!” she said as she panted softly, a trickle of drool running down her chin.

 

“I think that’d be more noticeable.” Momo told her.

 

“I knnnoooow, it’s just, this feels so goooood…! Ahhhn I wanna cummmm…!” the green haired girl panted. “Mo… Momoooo, so tell mEEEH, whY aRe you, so gOOd with sharING this dhiick!?” she asked, “I, haah, I need, to thINK of someTHING, else…”

 

Momo smiled, then blushed slightly, “Well, what I told Izuku is true, mostly… There is kind of another reason too…” she said as she slowly drew circles on the coffee table with her finger.

 

“TELL meeee…” Setsuna moaned, “NMMMMMMMMH, SO thiiiick, so FULL, feels gOOd, even when IT’S not MOVING!!!”

 

“Have you ever read an old manga called Senchi Muyoh?” Momo asked her.

 

Setsuna shook her head, grabbing a bottle of water from a table next to where she sat, twisting the cap off and chugging down the contents. Momo was glad Izuku was wearing his costume on set, it was made of a fabric that didn’t change shades when it got wet. Judging from how many times Setsuna moaned and shuddered, she’d climaxed at least half a dozen times already. The girls at Busteez liked to compare notes on how well a guy made them cum in the VIP suites. Nearly every girl there was a squirter when they REALLY came hard. Momo was no exception herself. The dark haired young girl could only imagine the mess inside Izuku’s pants right now. If he were wearing normal clothes, he’d probably look like he’d wet himself by now.

 

“I’m not surprised,” Momo said, continuing, “It’s a manga from my mom’s teenage years.” she told Setsuna. “It’s about this really nice boy named Senchi, your typical teen whose family runs an old shrine. Over the course of the story, several girls of varying levels of crazy all show up. At first they all fight him, or try to kill him, but in the end they all fall in love with him because of his kindness. This led to a lot of rivalry between the girls as they all fight each other now for his affection. Usually doing a lot of property damage along the way. But he won’t ever pick just one of them, because he knows that’ll break the heart of all the rest.”

 

Setsuna nodded, “Typ…ical, HAREM, manga…” she moaned.

 

Momo nodded, “Only by the end, the girls all grow closer, like sisters, their squabbles die down little by little and they are all united in their love for Senchi. Each one gave him healthy children and all of them lived together as a big family.” she explained.

 

“Oh, so one that actuALLY has an ENDing…?” Setsuna asked.

 

Momo nodded again, “Yes, and I… Well, I want that!” She told Setsuna, “To be a part of a harem for one guy, to be close to all the other girls who love him so much we become sisters. Sharing all the good and bad times, having arguments, making up, being just one big happy family!” Momo said as she stood up, looking up at the corner ceiling with her hands clasped together and sparkles in her eyes.

 

“Weeeell, it’s goOD to hAvE a gOAl!” Setsuna said and Momo turned to her with an excited expression.

 

“I already talked about it to Ochaco, and she’s okay with the idea! Tsuyu said she doesn’t know if what she feels for Izuku is love, but she doesn’t mind sharing him like that! Mina said she’s just down to screw around every now and then. So what about you!?” Momo asked her.

 

“Huh!?” Setsuna yelped as her body shook in orgasm once again.

 

“I can tell you like Izuku too, why else would you have offered to go through this for him?” Momo said as she came in close, her huge tits pressing around the phallic shaped distention in her belly. “How about it, would you help me make Izuku the happiest hero on Earth?!”

 

Setsuna’s entire face turned beat red, “What the hell, you sound like you’re proposing!?!” she yelled back, then grit her teeth together tightly, “HEEEEEEEEK, THOUGH I CAN’T SAY I”M OPPOSED TO GETTING THIS DICK EVERY DAAAAAY!!! CUMMING, CUMMING, I’M CUMMINGHH!!!!!!”

 

“Sure, I’ll put you down as a maybe then with Tsu-chan!” Momo said with a giggle. She then looked back at Izuku on the screen. Seemed the interview was finally wrapping up. They already had a plan for them to use his Float quirk to fly them back to the dorms which were closer than the Busteez Agency. Nearly everyone was out for the weekend now, so they’d have some privacy. Momo could only imagine how much pain he might be in now. She’d heard from Midnight that it’s not healthy for a guy to hold it in for too long. What did she call it, blue balls? Momo idly wondered if a man’s balls actually turned blue if he couldn’t cum for a long time?

 

---

 

“Nnnnngh…!” Setsuna moaned as Izuku pulled her pussy off his cock and handed it back to her. Momo was surprised, she’d half expected his dick to be a cherry red color by now, but it was still the same flesh tone with a pink tip it normally had. Mei wasn’t joking about her little performance enhancer being non-damaging, at least she hoped that was the case.

 

They were in Izuku’s room back at class 3-A’s dorm, Heights Alliance. Most of the other students were out, either on work study or just doing whatever they did on a free weekend. The only person she saw when they came in was Shoji who was reading a book quietly in the common area. He gave them a polite wave as they went by, but didn’t try to start any conversation.

 

“You okay?” Momo asked him.

 

Izuku nodded as he turned to Setsuna while she reconnected her body. “Thank you so very much for your help and I’m so very sorry you had to go through that!” he said in as polite a tone, one that Momo had never heard him use. Setsuna just stood there, her mouth hanging open slightly before she smiled, snickered, then laughed.

 

“It’s not like it’s your fault!” she said, still laughing. She then turned to Momo and wiped a tear from her eyes, “I see why you like him. I’ll give some real thought to what you said earlier.” she told her.

 

Izuku blinked, “Hmm, something happened?” he asked.

 

“It’s a secret!” Momo and Setsuna said together.

 

Izuku backed away slightly, falling back onto his bed and Momo smiled, “Anyway, does it, you know, hurt?” she asked, placing a hand on his still rock hard erection. Izuku’s cock twitched at her touch, making him gulp loudly.

 

“Well, not really, but it feels a little weird, and kinda cold now.” Izuku said.

 

“Well yeah, it just spent the last hour in my hot little hole, I bet coming out would be a little chilling!” Setsuna said, her voice just a bit smug. She then looked down at her abdomen, “Speaking of, you feel cold, but I suddenly feel all empty inside…”

 

“I know! I get that feeling too every time!” Momo said, grabbing Izuku’s cock and hugging it against herself. She smiled at the way Izuku shuddered. After all, she knew how much he enjoyed the feeling of her breasts against his dick. Even moreso now since she’d had Rie give them a nice fat boost to the same size she’d had the night he won his gold pass. Without even thinking about it, Momo quickly took off her top, exposing those huge tits and moving to wrap them around the thick shaft.

 

“Momo…!?” Izuku said.

 

“Well, you said it felt cold,” she said simply, “So I thought I’d help warm it back up.”

 

“Good idea, I’ll help!” Setsuna said, using her new quickband to simply strip herself naked before moving next to Momo, pressing her likewise enhanced tits against Momo’s. The dark haired girl giggled and smiled back at the other girl while they sandwiched Izuku’s dick between their big, warm, and soft breasts. Momo felt her nipples quickly turn stiff as they rubbed against Setsuna’s. The other girl’s nipples also got hard as the two of them began rubbing their breasts together, keeping Izuku’s dick in between them.

 

“Ha… Hang on, you don’t need… Oh, ooooh…” Izuku groaned, his protests fading quickly when the two girls quickly found a rhythm together.

 

Momo giggled, Izuku was just like that protagonist from the manga. She honestly for the longest time thought guys like him only existed in manga, not reality. It was one reason she fell for him so hard! She knew in her heart he’d never hurt her intentionally, there was no doubt whatsoever there.

 

Both girls giggled together as they began moving together, rubbing their breasts up and down Izuku’s length slowly. His cock was still slick from being inside Setsuna, so it was easy. Momo loved the way he groaned softly due to their service and leaned her head in close to kiss the tip of his cock. Setsuna then mirrored her movement, and the two girls began peppering his length with kisses all over the tip of his dick.

 

“Ahhnnn, so big…” Setsuna cooed softly as she extended her tongue and began slowly licking the upper length. “I can still feel it inside…”

 

Momo giggled, she understood that feeling as well. Every time she had sex with Izuku, she could feel the sensation of his cock inside her for several hours after. And after having this beast inside her for over an hour, Momo could only imagine how long that feeling might last!

 

“Nmmmmmh, AHHHMMMPH…” Setsuna moaned softly, opening her mouth wide and taking the tip of his cock between her lips. Momo watched as the dark green haired girl slowly took Izuku’s length in, moaning softly when the rigid flesh pole was shoved down her throat.

 

“Oooooh…” groaned Izuku as Setsuna took in as much as her angle allowed before pulling her head back up slowly.

 

“NMMMMPH…!” she then moaned again, pushing her head back down, then pulling back up, then moving down again. Her pink lips made a soft wet slurping noise every time she lifted her head back up. Momo watched, the steamy view making her feel a strong heat between her legs. Her mouth hung open slightly as she gazed longingly at Izuku’s thick dick.

 

‘Ahh, I want it…’ she thought, ‘I wanna suck it…!’ Setsuna seemed to almost read her thoughts and suddenly relinquished Izuku’s dick, the tip making a hollow ‘pop’ as it flung away from her lips and into Momo’s mouth.

 

Delicious!

 

It was the only word Momo could think of to describe the taste, the smell, the feel of this big, hot, hard cock in her mouth! Her jaw instantly ached from the thickness, but she loved that feeling too as she began moving her head up and down quickly.

 

“AAAHNNN, ISHUUKUUU… UR CAWK… SHO PHIICK, SHO GUUD, AHHHNNN, I WUV ID…!” Momo moaned, taking his cock as far down her throat as she could. She felt her neck bulging from the sheer girth of his dick and moaned loudly around it.

 

“NMMMPH, HMMMPH, GUH, MMMMPH GUG, NMMHMMMMPH, AGUH, AYE WUV DISH PHEELING, MUH MOUPH PHEELSH GUUD, SHO GUUD, WANNA SHUCK ID MOAR…!” she moaned.

 

Next to Momo, Setsuna squirmed lightly, still rubbing her breasts against the dark haired girl’s as she licked her lips, “Wow, watching you do that is kinda hot…” she breathed softly. She then pulled away just a little, “I’m gonna make out with your boyfriend a bit, you just keep on doing that girl!” she told Momo.

 

“NMMMHMMMMPH…!” Momo moaned happily, moving to kneel between Izuku’s spread legs, claiming his entire cock between her tits when she saw Setsuna move farther up on the bed.

 

“Setsunaahmmmph…!” Izuku began to say before his words were cut off when the other girl kissed him fiercely. Momo could feel his cock throbbing in her mouth as she heard Setsuna moan softly over the sounds of their lips and tongues smacking.

 

“NMMMMMPH, MMMMMMPH, HMMMMMPH, AGUH, HAAAH…!” Momo moaned, lifting her head free and licking Izuku’s cock from the balls to the tip before sucking it back down her throat. She then allowed her huge breasts to fall away from his length and took it all into her mouth, burying her nose in his pubic hair. “AGUUUUUUH…!” she gagged and moaned around his cock, making sure to vibrate her throat thoroughly.

 

She felt Izuku shudder in pleasure and looked up to see Setsuna and him looking back down at her. Setsuna smiled and moved to whisper into his ear, “Nmmmmmh, doesn’t she look so sexy right now, her pretty lips wrapped around that big monster dick. I bet you can feel the bottom of her stomach now, can’t you?” she asked him.

 

“Haaah, ye… Yesss…” Izuku hissed.

 

“Does it feel good?” she asked him in that same husky whisper. He nodded and closed his eyes tight as Momo felt his cock throbbing in her mouth, throat, and belly.

 

“Then tell her!” Setsuna told him, still whispering before moving to lay beside him, “Tell her how good she’s making you feel.”

 

“Ahhaa, I… It feels… Good… It feels so good…!” Izuku groaned, “D… Don’t stop…”

 

“Good boy…” Setsuna whispered before gently biting the edge of his ear with her sharp teeth, making him groan again.

 

“NMMMMMPH!!!” moaned Momo, moving her head faster now, sliding her lips up and down his length sucking it roughly every time her head bobbed up. “HMMMMMNPH, GUG, NMMMMMMPH, GUH, AGUMMMMMMPH, GWEGH, MMMMMMMPH, GURKLE…” she gagged and moaned deep in her throat, her eyes looking up at Izuku’s. She then held eye contact with him as she lifted her head away completely. The dark haired girl then leaned her body back down to kiss the base of his cock, then slowly planted kisses along his entire length before licking the tip softly.

 

“I love you…” she said, meaning every word of it as she moved to take his cock inside her pussy. It was SO hard, and thick, and long, like having a soft leather covered steel rod being pushed inside, but Momo loved the feeling. Her flat and toned stomach bulged up and out in a perfect outline of his dick as he slipped into the depths of her womb.

 

“AHHHNN, IZUKUUU, I LOVE YOUUUUU…!!!” Momo screamed, cumming the instant her butt came to rest against his huge cantaloupe sized balls. She grabbed her own breasts, squeezing them roughly as she found herself imagining Ochaco and Tsuyu each claiming one of her nipples to suck on! She knew boys got off seeing girls go at it with each other, and Momo was rather turned on by the idea as well. She slowly rolled her hips, making his cock stir around inside her. It felt as though her insides were being rearranged, but it felt so good as well.

 

When he reached his arms up, Momo let go of her breasts, ready to surrender them to him to play with as much as he liked. She then yelped softly when instead he put his arms around her, pulling her down so that they were face to face. When he spoke, Momo thought for a moment her heart had simply stopped.

 

“I love you too…” he said before kissing her hard.

 

An orgasm more powerful than anything she’d ever felt before shot through Momo like one of Kaminari’s electric bolts. She moaned in utter bliss against his lips as their tongues met, then began to wrestle one another as though they were in a battle to the death! She sucked on his tongue hard, her arms moving to wrap around his shoulders while the two of them moved in unison, slamming their bodies into the others. Momo felt as though she was being turned inside out every time Izuku pulled out even a little, only to ram his cock back inside, giving her a feeling of completion that sent her into ecstasy again and again and again!

 

The two rolled on top of the bed until he was on top of her and Momo wrapped her legs around his waist, trying to lock their bodies together. “AHHHHNNN, DON’T STOP, OH GOD!!! YES, YESSS!!! HARDER, PLEASE IZUKU, HARDERRRRNNNNNMMMMMH!!!!” Momo howled in pleasure as she felt and saw the sparks of green lightning zapping around his body while red lines of energy spread across his skin like cracks.

 

“OOOOOHHHHH, GAAAAAWWWD!!!!!” Momo screamed, cumming from his every movement as he used One for All to fuck her harder! The SMACK SMACK SMACK of their bodies colliding was almost too much! Momo felt as though she might pass out every time he pushed back in, but she never wanted him to stop! Their mouths connected again, tongues fighting one another for dominance while she bucked her hips into his thrusts.

 

“ISHUKU, ISHUKU… NMMMMMMH…!!!” Momo moaned into his mouth at the same time that she felt herself cumming again, her entire body tensing up, then relaxing in a wave of ecstasy. She then felt Izuku tensing inside her, followed by a rush of thick liquid warmth that flooded her insides.

 

“Oooooooooooh…” Momo moaned in pleasure, her back arching as Izuku broke their kiss, sitting up on his knees as he came inside her. “So, full…” Momo moaned, “Dh… Dhon’t stooop… Fill me uuup…” she whimpered weakly, still cumming just from feeling the copious amounts of cum pumping into her.

 

“Mmmmmh, fuck that’s hot!” Setsuna said while laying next to the pair, one hand between her legs, her fingers dipping in and out of her sloppy pussy furiously.

 

When it was finally over, Izuku pulled out of Momo slowly, causing a huge rush of cum to pour out of her sounding similar to when you upended a water jug. The mess was horrible, and Momo made a mental note to have his sheets cleaned for him.

 

Izuku lay on one end of the bed, his still rock hard cock throbbing in the air, reminding Momo that he was gonna be stuck like that for a good while. When the cum had finished draining out of her stretched pussy, she sat up on her knees and smiled at him warmly. She then crawled naked over to him and gave him a passionate kiss, sucking on his tongue lovingly as he kissed her back.

 

“Hey, no fair, if there’s gonna be a harem, then you gotta share Momo!” Setsuna said.

 

Breaking the kiss, Momo giggled, “You’re right, sorry!” she said with a grin.

 

Setsuna grinned back at her, but Izuku blinked in confusion, “Huh, what harem?” he asked.

 

Momo turned back to him and smiled, “Oh, about that, you see…”

 

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Story by Sailor Io