Anti-NTR Man: Tomboy Sister Bully

' - Thoughts.

" - Speaking out loud.

Introduction

Hello! This is a fanfiction based on the NTR manga Tomboy Sister Bully by Ratatatat74.

Yuuto Sakurai is an original character from my web novel Anti-NTR Man, which has 80 chapters as of writing this. I've already written a fanfic where Yuuto enters an NTR universe once before and thought it would be fun to do it again.

Warning: I'm experimenting with a new style here, so I'm mostly winging it! The story will focus on power and social dynamics, which is a new area for me. Please keep that in mind if things aren't perfect.

With that said, enjoy the story!

CHAPTER 1: ANTI-NTR ISEKAI

SLAM! The sound of a wooden drawer being forcefully closed echoed through the room.

Yuuto had just stashed away his latest "masterpiece," a work he'd admired for over an hour.

Yes.

Another NTR redemption fanfiction, one of the thousands he wrote in his free time, where he inserted himself as the ANTI-NTR MAN—the hero who saves the main character from being NTR'd.

That was his identity. His purpose. His... curse.

... His delusion.

"BECAUSE MAIN CHARACTERS ARE TOO WEAK! THAT'S WHY SOMEONE LIKE ME HAS WORK!!! WHOOOOO! LET'S GOOO! GIMME MONEY!!!" He shouted at the ceiling, failing to acknowledge that not a single person had visited his site or paid for his dubious services.

"Dubious? HAH! The only dubious thing is how many people are getting NTR'd and not calling ME!" He boasted to no one, grabbing a fresh sheet of paper and readying his pen.

'While I wait for the INEVITABLE CLIENT WHO WILL HIRE ME, I'll craft another MASTERPIECE! Each one sharpens my already superior mind!' He thought, deluding himself.

"Hmm..." He muttered, staring at the blank page. "I need some inspiration..." Minutes passed without a single idea.

Turning to his computer, he began a search.

Two hours later...

"Hmm..." he hummed again, scrolling through a certain piece, eyes glazed over. "It's pretty mild," he murmured, clearly unimpressed.

"As someone with a bratty sister, I honestly wouldn't care if some bastard made a whore out of her. She's such a pain, I'd be surprised someone even bothered to try. Heck, I might even be proud of the guy, in a way that he actually did it... And if that same guy tried to bully me, I'd just baseball his ass... Or maybe not. Gotta keep my cover as a SUPERHERO, like Karlc Knet, the Supreme-Human Man."

Yuuto sighed, clearly disinterested.

"Is this really even an NTR? This feels more like a regular bully story, not NTR..." he muttered to himself.

"I mean, it's just his sister. It's not like the main character was planning on screwing her anyway." He grimaced. "Yuck. Imagine being so fatherless that you'd want to bang your own sister."

"Whatever. Pass." He clicked away from the story. "Nothing interesting here... Not even—"

Suddenly, a baseball smashed through his window, hitting him squarely on the head. Yuuto slumped onto his keyboard.

"WHAT THE—WHO!?" He snapped awake, abruptly finding himself sitting in the middle of an empty basketball court.

Yuuto looked around, his mind spinning. He quickly noticed he was no longer in his room but in an abandoned basketball field, not a soul in sight.

His hair fell into his eyes—long, unkempt locks that hindered his vision.

'To think I got ambushed... GRR!! HOW CARELESS!!' Yuuto mentally scolded himself, feeling the ache in his abdomen. Several areas felt bruised, some completely numb.

'Well, as the superhero I am, it was only a matter of time before the NTR villain group captured me. I must stay vigilant,' he thought, taking a deep breath.

'First things first. Nothing feels broken... but I should do a full body scan, just to be sure.' He brushed his hair out of his eyes, his vision clearing.

He struggled to his feet—thankfully, no pain in his legs.

'Now, I just need to find a mirror,' Yuuto decided, spotting a public restroom nearby.

'Man, if only I could tell what's broken just by instinct, like in anime. Gotta learn that power someday.' He shook his head, stepping inside, and after confirming it was empty, he removed his shirt, eyeing himself in the mirror.

'Shit...' He clicked his tongue, examining the bruises covering his body.

"WHO THE HELL IS THIS TWINK!?" He yelled, leaning against the sink in a panic.

'This can't be real... No, NOOO...!'

"AGAIN!? REALLY!?" he shouted to the ceiling.

"IF I HAD A COIN FOR EVERY TIME I TRANSMIGRATED INTO A WIMP'S BODY, I'D HAVE TWO COINS! WHICH ISN'T MUCH, BUT IT'S WEIRD THAT IT HAPPENED TWICE!!!" he ranted.

"COULDN'T YOU PUT ME IN 'THE BOULDER'S' BODY FOR ONCE!?" he shouted before doubling over, his sides aching.

"Tsche..." He gritted his teeth, glaring into the mirror.

'Still... these injuries are no joke,' Yuuto mused, his expression softening slightly. 'This is just my educated guess, which means it has to be right; Whoever did this... enjoyed it. Most are fresh, but I can see at least a dozen that aren't.'

He glanced down at his now-noodle arms, that mattress of a chest, and the sheer bones sticking out. 'I'm in the body of a wimp who's getting bullied, right? That has to be it, and judging by how young this shrimp looks, I'm in... Around first year of High-School?'

His brow furrowed as he thought about the precision of the injuries. 'The bully knew what they were doing—hitting spots where the bruises wouldn't show easily. Was this kid keeping quiet out of fear? Or care for his family?'

Yuuto took a deep breath, slipping his shirt back on. 'No point mulling over it. I need to find out where this wimp crashes. It's getting dark.' He patted down his pockets, noticing a phone.

'Lucky.' He unlocked it easily. 'Now, who do I call...?'

He scrolled through the contacts, scanning the labels: "Mom," "Sis." Yuuto sighed. 'Of course, fatherless.'

'Oh?' His thumb hovered over another contact labeled "Friend."

'So, he had a confidante, huh? Rather than call his mom or sister, maybe I should call this guy. I could just go all: 'HEEEEEY BUDDEH, I GOT MAD DRUNK AND SLAMMED MY BODY AGAINST A GUARDRAIL IN MULTIPLE PLACES, COME PICK ME UP~~~'' He thought, smirking at the idea.

But then, he paused. 'Wait, am I stupid (obviously not)? I just got transmigrated into a wimp's body after getting beat up. Where was this "friend" when it happened?'

His curiosity piqued, Yuuto scrolled to the messages section. 'I should check their interactions first...'

Yuuto's eyes widened as he started reading through the messages.

Main Character:

"Hey... can we talk?"

Friend:

"Sure, what's up?"

Main Character:

"I... I just wanted to ask if you could maybe, um, stop pushing me around? It's... getting kind of hard to deal with."

Friend:

"Pushing you around? Man, what are you talking about? We're just messing around. It's not serious."

Main Character:

"Yeah, I know, but... it hurts. You know, sometimes."

"Like, when you hit me last week... I'm still bruised. I just don't understand why you're doing it..."

Friend:

"You think I'm trying to hurt you? That was nothing. You're blowing this way out of proportion. I didn't even hit you that hard."

Main Character:

"I know... I mean, I'm not saying you did it on purpose, but it's just... hard to hide the bruises now. My mom's starting to ask questions, and..."

"I just don't know what to tell her."

Friend:

"Bruises? From me? Come on, man. Maybe you're just clumsy. I saw you trip over your own feet the other day. You're always bumping into things."

Main Character:

"No, I... I mean, I guess, but... I don't trip that much. You've been hitting me, and I can't keep making excuses for it."

Friend:

"Dude, you're really overthinking this. Friends mess with each other all the time. You're not mad, are you? It's just a joke, we always joke around."

Main Character:

"No, I'm not mad, it's just... I don't know if I can keep dealing with it. Could we... maybe stop?"

Friend:

"Stop what? Stop being friends? Is that what you want? You're saying you don't want to hang out anymore?"

Main Character:

"No, I... I didn't say that. I just... I don't know."

Friend:

"Look, man. You need to chill. You're acting like I'm some kind of villain. It's not like I'm trying to hurt you. We're just having fun. Maybe you're just a little sensitive, huh?"

Main Character:

"I'm not sensitive... I just... I don't know. I just want it to stop."

Friend:

"Alright, alright. I get it. You're stressed. I'll back off, okay? But you don't need to go around telling people about this. You don't want your sister to find out, right?"

Main Character:

"My sister? Why would she need to know?"

Friend:

"I'm just saying, you don't want to make things awkward. She might think you're weak, that you can't take care of yourself. Do you really want her to worry about you?"

Main Character:

"...I guess not."

Friend:

"Exactly. She's been hanging out with me lately, you know. We've been getting close. Do you really want her to think you're too fragile? Come on, man."

Main Character:

"I... I didn't know you were hanging out with her."

Friend:

"Yeah, she's cool. We get along. You wouldn't want to mess that up, would you?"

Main Character:

"No, but... just leave her out of this. Please."

Friend:

"Relax. I'm not gonna do anything to her. But you don't want her getting involved, right? Let's just keep this between us, and everything will be fine. You don't need to tell anyone."

Main Character:

"Okay... I won't say anything. Just... stop hitting me, okay?"

Friend:

"Sure, sure. But hey, delete these messages. We don't need anyone seeing them. Just do that for me, alright?"

Main Character:

"...Yeah, I'll delete them."

"Woah..." Yuuto gasped as he scanned the messages, his knees giving way as he collapsed to the bathroom floor.

"This... This is just..." His breath quickened, and his phone slipped from his trembling hand.

"I recognize this pattern... The manipulative nature... The sister he mentions, and now this..." His eyes widened, the realization dawning on him.

"It's... that doujinshi I've read...!" he murmured. His excitement grew.

"I'm... I'm really in it again...!"

He raised a fist to the sky, as if heralding some grand cosmic irony. "AN NTR MANGA!!" He almost smiled widely, his voice brimming with dramatic energy.

"I can finally baseball..."

"I can baseball..."

But the anticipated rush of glory fizzled out just as quickly. His enthusiasm drained.

"... But there's no one to baseball," he muttered, slouching as the weight of the situation settled in. "I'd take it if it were a lover or something, but she's this body's blood-related sister. What am I supposed to do? Take care of a bully if he tries messing with me again? That's it? Because I sure as hell ain't gonna make the sister fall for me instead... EW. She can fuck whoever she wants." Yuuto's face darkened, his earlier joy gone.

"No... there has to be something more." He whispered to himself, pulling himself upright again, determined. "I was brought here for a reason. The wheels of fate (the high-on-copium author) brought me here for a reason...!" He repeated. "There has to be more."

He scrolled through the messages again, and a few key words lingered in his mind: Friend. Manipulative. Liar. Sadistic.

Now, the pieces started to fall into place.

'Now that I think about it... In the manga, he said how he loved watching the MC squirm, taking his masculinity away bit by bit. The type who loves to come out on top, a manipulator drunk on his own power, with an ego as fragile as his smirk.'

'... Let's assume for a second that the main character gets used to the treatment he's been getting. When that Friend sees the relief in his eyes, do you think he'll just stop? Leave him alone and keep playing with his sister? WRONG!' Yuuto's mind raced, his thoughts becoming sharper, darker.

'HE'LL WANT MORE. HE'LL NEED MORE HARM TO KEEP GETTING THAT SAME HIGH! The rush of control, the thrill of dominance—he'll have an egotistical injury when he sees the routine and perseverance in the main character's eyes. And that mental injury.... Will cause him to crave something new.'

Yuuto's grip on the phone tightened, his eyes narrowing as his reasoning took a sinister turn.

'And since this guy clearly has a thing for pretty women... who's to say he won't go after the wimp's mom next? She's the last light in the MC's life, the only source of comfort. If he takes her away, what will that do to him? Squirming beneath his heel again, even more helpless...'

'But more important more than anything...! THAT BASTARD CAN GET ME KICKED OUT OF MY OWN HOUSE!! I CAN'T ALLOW THAT! I WANT TO FREELOAD!!!'

Yuuto shamelessly admitted as he clenched the phone tighter.

'Hmpth,' He grunted, his focus returning 'Someone who gets off on making the weak tremble beneath him. No remorse, just pure control as he rises to the top... with no obvious weakness, at least at first glance.'

A smirk crept onto Yuuto's face, sharp and wicked.

'Someone like that... He only exists in an NTR manga. He's a textbook machiavellian...'

'And a perfect antagonist to get baseball'd by ME.'

His smirk widened into a subtle grin as he glanced back at the phone.

'Careful, Friend. I might just knock you off your imaginary throne.'

[AUTHOR HERE. THOUGHT I'D TRY TO WING IT AGAIN. SEE HOW THAT WORKS.]

[MIGHT CONTINUE, MIGHT NOT IDK]