My Harem System In My Hero Academia

"Welcome to today's live performance!" screamed the Pro Hero Present Mic, his voice blasting through the massive auditorium speakers. "Everybody say HEY!"

There was dead silence.

Present Mic didn't seem bothered by the lack of enthusiasm. "Well, that's cool. My examinees, listen! I'm here to present the guidelines for your practical! Are you ready!?"

More silence.

Yami sighed, leaning back in his seat. He'd already tuned out most of the presentation. Present Mic's energy was... certainly there, and the whole situation felt pointless.

He sat a row above two familiar faces—Midoriya and Bakugo. Midoriya was muttering under his breath, probably analyzing every word of the instructions, while Bakugo sat with his usual scowl. He looked abnormally calm for his character, but Yami thought it could be worse.

Yami scanned the room, recognizing a few faces from his vague memories of the story. 

There was a broad guy with a rock-hard face—Kirishima, if he remembered correctly. A pink-skinned girl with horns. A guy with glasses who looked like he was trying too hard to act like a perfect student.

'What's his name again?' Yami thought, rubbing his temple. 'Ida, right?'

Yami barely paid attention to Present Mic's rambling until he heard a sharp voice cut through the auditorium towards his direction.

"...And you! With the curly hair!"

Yami's eyes snapped to the source of the voice.

It was Ida Tenya. Tall, with short dark blue hair neatly parted on the right side and a tiny shaved patch near the base of his head. His square jawline and stiff posture gave off the vibe of someone who lived by the rulebook.

"You've been muttering the whole time!" Ida barked, pointing at Midoriya. "It's distracting!"

Midoriya froze, his mouth opening and closing as he tried to stammer out an apology.

Ida wasn't done. "This is a formal examination! You should conduct yourself with more decorum and refrain from disturbing others!"

Before Midoriya could say anything, Yami decided he'd had enough; today, he was in the mood to antagonize someone.

"Leave the poor guy alone," Yami said, calm but firm.

Ida's sharp gaze flicked to Yami. "And who are you to interject?"

Yami didn't flinch. His golden eyes locked onto Ida's with a steady intensity.

"Ida," Yami said, his tone dry. "Now sit down and focus on the presentation; you are wasting everyone's time."

Ida's jaw clenched, his glasses catching the overhead lights as he straightened his posture. He looked ready to argue but was interrupted by Present Mic's booming voice.

"Alright, alright! Quiet, both of you! Examinee 7111—nice catch. Thanks for keeping things on track!"

Ida adjusted his glasses, clearly irritated, but he sat down without further comment.

Yami sighed, leaning back in his chair. 'Momo's definitely going to give me hell for this, he thought'. She hated it when he got into unnecessary confrontations, especially in public.

As he settled back, Yami caught Midoriya glancing at him from below. There was something in the kid's eyes—respect, maybe even admiration.

It made Yami's stomach turn.

He met Midoriya's gaze with a sharp, cold look. 'Fuck off,' his eyes said.

Midoriya quickly turned back around, sinking into his seat.

Present Mic continued his over-the-top explanation of the practical exam, discussing the various zones and the point system. 

Yami tuned most of it out. He already understood the basics: smash the robots, score points, and impress the judges.

It was simple enough.

As the presentation wrapped up, the students began filing out of the auditorium toward the exam areas. Yami followed the crowd, his mind already shifting into battle mode.

He spotted Midoriya walking ahead, looking nervous and clutching a notebook. He then tripped over his feet, barely catching himself before face-planting on the pavement again.

"Pathetic," Yami muttered under his breath, shaking his head.

The gates to the fake city loomed ahead. The towering skyscrapers and buildings with elaborate setups were meant to simulate real urban environments. 

Yami glanced around, assessing the competition. Most of the students looked tense, and some seemed a push away from collapse.

Yami cracked his neck, rolling his shoulders.

'Well, It could be worse', Yami thought.

After passing through the gates, the professors quickly separated everyone into groups. To Yami's dismay, he ended up in the same group as Midoriya and that bubbly brunette, Uraraka.

Yami sighed in frustration. "Of course," he muttered to himself. Just as he thought he could catch a break, Ida's familiar, uptight voice was heard again, scolding Midoriya for something. 

Yami didn't bother looking. He could already picture the scene—Ida waving his arms around like some self-important asshole and Midoriya shrinking in on himself, stammering apologies.

This time, Yami wasn't interested in playing the hero for the green-hair. He simply walked away from the commotion and spaced away, thinking about Angela... Yeah, he was going to fuck her tonight; he needed to raise Lust anyway.

His golden eyes scanned the fake city's towering buildings and maze-like streets when Present Mic's booming voice snapped him out of his thoughts.

"...And... Begin!"

Yami didn't need to be told twice. He launched forward with explosive speed, dashing past the distracted students. His heart pounded with adrenaline, but his mind remained cool and calculated.

The street he entered was crawling with robots. His eyes quickly assessed the situation.

'One, two, five, seven... eleven robots,' Yami counted, his lips curling into a grin. 'That's twenty points just waiting to be taken.'

For years, Yami relentlessly trained with his quirk. He had long since realized that petrification wasn't the core of his ability—it was merely a byproduct of something far more profound. His true power lay in his ability to manipulate his body down to the cellular level.

It had taken years of brutal, self-imposed training to hone that skill.

Every day followed the same grueling routine. After attending middle school, Yami would spend hours training with Momo in the Kendo and Fencing clubs. 

After that, he'd study with her for hours again and return home to eat dinner and please Angela as a woman.

But it was in the dead of night, when the world was silent, and he was alone with his thoughts, that Yami pushed himself to the brink of insanity.

In the privacy of his room, Yami would grab one of Momo's tungsten batons—the same type she crafted with her quirk to beat him up from time to time—and begin his unique training. 

Yami would strike himself with it, over and over, breaking his ribs and fracturing bones. 

He used his quirk to repair the damage each time, feeling the bones knit themselves back together through sheer will and focus.

The pain was excruciating. But pain, Yami had learned, was the best teacher.

His nightly torment led to the development of his first self-made technique—something born not from the system but from his own relentless will.

[Quirk Technique Unlocked: Open Bones]

Yami had discovered he could control the movement of his bones, manipulating them like external weapons or limbs. 

The first application of this technique focused on his ribs. [Open Ribs] allowed Yami to extend his ribs outward from his body, spinning and twisting like deadly tendrils.

The ribs could stretch to a maximum length of 187 centimeters and exert a crushing pressure of up to 1325 kilograms per square centimeter. 

The bones could spin, twist, and move in any direction, as deadly spears or crushing pincers. 

To increase their effectiveness, Yami could petrify the ribs before impact, sharpening them and making them nearly unbreakable.

In an instant, Yami activated [Open Ribs].

The bones in his chest twisted and shot outward like spears, impaling all eleven robots in the street. 

The metal husks exploded into shrapnel, sparks flying as their circuits fried.

Yami stood amidst the "corpses" of the robots, his chest panting. Blood leaked from his shirt where the ribs had torn through his skin.

The downside to [Open Bones] was brutal—each time he used it, his own bones would rip through his muscles and organs. 

The damage was severe and could easily cause him to pass out from shock if he didn't heal quickly.

Without hesitation, Yami petrified his chest, stopping the bleeding and instantly regenerating.

But there was another problem.

Angela's special cream, the only thing protecting him from the sun's harmful effects, was destroyed wherever he used [Open Bones]. 

His exposed skin became hypersensitive to sunlight even more than it already was. 

Until he reapplied the cream, he'd have to keep those areas petrified to avoid burning alive.

Yami wiped the blood from his chest and looked around the wreckage. "Still standing," he muttered with a smirk as he touched his petrified chest. "Good enough."

He moved through the city, destroying more robots as he went. His pace was steady but efficient, and he focused only on the robots with a higher point denomination. 

In one alleyway, Yami encountered a pink-skinned girl with horns and a rack that could challenge Momo's in firmness but still lacked some size.

"Need a hand?" Yami asked casually, noticing her struggling with a cluster of bots.

She gave him a quick glance, but the moment her eyes met his and lowered to his body, she was clearly impressed by his muscular frame. "Sure thing, big guy."

Yami quickly dispatched the remaining robots with just two ribs, earning her a grateful smile. "Thanks! Name's Mina Ashido."

"Iwatani Yami," he replied, flashing a quick grin. "Nice to meet you."

As they parted ways, Yami felt the ground rumble beneath his feet. His eyes moved upward, widening as he saw the massive silhouette of the Zero Pointer towering over the fake city.

"Aren't you some delicious dessert?" Yami muttered as he ran over to the robot at the eye of the storm.

.

.

.

Somewhere in a dimly lit observation room, three professors sat silently, their attention fixed on a single monitor. 

Unlike the rest of the faculty, who watched the broader field of examinees, Eraserhead, Midnight, and Nezu had focused on one student: Iwatani Yami.

Eraserhead's eyes narrowed as he leaned closer to the screen, watching intently as Yami obliterated a cluster of robots. 

His ribs—long, spear-like white bones—shot out from his chest with unnatural precision, impaling the machines before retracting back into his body. 

Moments later, blood seeped through Yami's torn shirt, staining it red. Yet, without hesitation, he petrified his chest, sealing the wounds and continuing his rampage as if nothing had happened.

"He's bleeding profusely," Eraserhead noted, his tone calm but sharp. "Most kids would be down for the count after an injury like that. He's not even flinching."

Midnight, lounging on the armrest of her chair, let out a low hum of appreciation. 

Her gaze lingered on Yami's muscular body as he ran through the fake city, brutally dismantling more robots. His shirt, tattered and soaked in blood, clung to his sculpted chest, revealing the hard-earned definition of his muscles. 

A mischievous smile crossed her lips when Yami switched to barehanded combat, smashing bots with raw force.

"He's very well-built for his age," Midnight purred, tapping a finger against her chin. "Handsome too. If he's this jacked at sixteen, imagine what he'll look like at eighteen. Quite the specimen…"

Eraserhead shot her a sideways glance, his expression flat. "Focus, Midnight."

"Oh, I am," she teased, her eyes never leaving the screen. "Believe me."

Nezu sipped his tea, unbothered by the banter, before setting his cup down with a soft clink. 

"Iwatani Yami," he began, his tone thoughtful. 

"A graduate of Fujimoto Private Academy in Tokyo. Consistently ranked second in academics and first in physical evaluations. The only student ahead of him was Yaoyorozu Momo."

Eraserhead raised an eyebrow. "Second place? He doesn't strike me as someone who plays second to anyone."

"Indeed," Nezu agreed. "Yet, it's a curious detail. Despite his academic performance, his quirk remains largely undocumented. The school listed it simply as 'Pillar Man.'" 

Nezu tilted his head, curiosity in his beady eyes. "A mutation-type quirk, capable of turning his skin into an obsidian-like object and healing any wound almost instantly while absorbing sunlight at such rates if his skin is exposed for too long, it would evaporate. He is capable of going days without substance or rest, fascinating."

Eraserhead crossed his arms. "What about his family? Any red flags?"

Nezu's expression grew more serious. "The Iwatani family is well-regarded in corporate circles. His mother, Angela Iwatani, now manages Iwatani Industries after the mysterious death of her husband, Iwatami Akio. It's said that Yami keeps a low profile, but there are whispers—"

Nezu trailed off as the screen showed Yami tearing through another group of robots. His ribs once again extended, twisting like serpents to decapitate multiple machines before retracting with a sickening snap. 

The force of the attack sent shrapnel flying, but Yami remained unfazed, even as blood trickled from reopened wounds. His expression remained stoic; after ensuring the robots were done for, he dashed away for his next prey.

"Whispers of what?" Eraserhead pressed.

Nezu folded his hands neatly in front of him. "Whispers that he's far more dangerous than anyone realizes."

Midnight chuckled, brushing a lock of hair behind her ear. "Dangerous and gorgeous? Oh, this year's going to be fun."

Eraserhead sighed, clearly irritated by her antics. "He's a kid."

"A very interesting kid," Nezu added, his gaze fixed on the screen. "And I believe it's about time we see how this batch handles the next challenge."

Nezu reached for the control panel, his tiny paw hovering over a button marked with a bold "YARUKI SWITCH"

"Let's see if they can handle the unexpected," Nezu murmured, pressing the button.

The screen flickered, shifting to show the towering form of the Zero Pointer rising from the depths of the fake city, casting a massive shadow over the battlefield.

"It begins now."