A thick silence filled the air. Every hero and villain on the battlefield, already on edge, could feel the atmosphere grow tense. The confusion between master and pupil was palpable. The realization of deceit played across both their expressions.

Shigaraki's mind raced. He cast his eyes around the area, his thoughts settling on a particular individual. "Where's Aiko?" he demanded, but there was no answer.

Momo, feeling the urgency of the moment, took a step forward. "Whoever did this, it sounds like they played both sides."

Nejire added, "Seems like someone wants to see both I-Island and villains fall."

All Might's gaze was fixed intently on All for One. "Regardless of who did what, you're here now, and you need to answer for your actions."

All for One smirked. "Always so noble, Toshinori. But it appears even I can be deceived."

"Let's end the fight we started years ago," All Might said and charged forward, his biologically altered body allowing him to fight with the full strength he possessed in his prime. His fist swung through the air, aimed directly at All for One.

All for One responded with a flick of his wrist, unleashing various Quirks he'd stolen over the years. A powerful gust of wind met All Might's attack, pushing him back with immense force.

"You still think you can defeat me, Toshinori?" All for One sneered, his eyes narrow and calculating.

"You underestimate me," All Might growled, his muscles tensing as he prepared for another attack. "I'm not the man you once fought."

Meanwhile, All Might and All for One clashed again, their battle raging on with no sign of slowing. Every strike from All Might was met with a counter from All for One, the villain's stolen Quirks creating a nearly impenetrable defense.

Meanwhile, a wave of energy broke Shigaraki from his confines. The villain's eyes widened as he found himself free, his hands reaching out, ready to unleash his deadly decay.

"Give up, Toshinori," All for One taunted, his voice dripping with arrogance. "You've lost your power. You're nothing without One for All."

"I'm still here!" All Might roared, his voice filled with determination. "And as long as I draw breath, I'll fight to protect those I care about."

The two continued to clash, the ground shaking with the force of their battle. All for One's Quirks whirled around him, a maelstrom of abilities that seemed to anticipate All Might's every move.

"You're still predictable," All for One sneered, landing a blow that sent All Might staggering back.

"I'm not done yet," All Might spat, launching himself forward once more.

The battle escalated quickly, as All for One unleashed a torrent of various abilities he had stolen over the years. The surface of I-Island was in ruins, buildings crumbling and streets torn apart. The heroes found themselves in an unexpected position – having to shield the very villains they had captured from the overwhelming onslaught.

Out of nowhere, the shrieking roars of the High End Nomu echoed through the battered landscape. All Might, with his returned vigor, Mirko, with her swift agility, and Ryukyu, in her dragon form, converged on them. Their combined strength was barely enough to hold off the grotesque abominations.

"Take care of the people we caught!" All Might shouted to Nejire and Sahar as he charged headlong into a group of Nomu, throwing punches with the strength he was once renowned for.

Sahar focused intently, her unique ability allowing her to sense even the slightest disturbances in the area. "Nejire, three injured to your right!"

Nejire, without hesitation, soared towards them, her ethereal energy wrapping around the wounded, protecting them from further harm.

The epicenter of the battleground was reduced to a crater, dust and debris obscuring vision. In its center stood four figures: Mokami, with Momo steadfastly behind him, Shigaraki, pain evident in his eyes, and the imposing figure of All for One.

Shigaraki coughed, drawing attention to his battered form. "Sensei," he rasped, eyes darting between Mokami and All for One. "Why are we fighting them?"

All for One turned, a slow, deliberate movement. "It's not about them, Tomura. It's about proving our might, proving our ideals."

"But… at what cost?" Shigaraki's voice trembled, full of doubt.

"Cost?" All for One chuckled. "Sacrifices are necessary for change."

Momo, her voice clear and firm, interjected, "Is that what you tell yourself to justify your actions? You’re nothing but a tyrant!"

All for One’s head tilted slightly, "Young lady, it's not about justification. It's about ambition."

During their interaction, Shigaraki's eyes began to narrow, his gaze fixed intently on Momo and Mokami. The way Momo's hand clenched at the fabric of Mokami's suit, the way she moved just a fraction closer to him when All for One's attention was elsewhere, the way her eyes lingered on Mokami even as she addressed the enemy before them. A realization crashed upon him, causing his heart to skip a beat. The subtle gestures between Mokami and Momo — the way she subtly moved to stand protectively in front of him, her fingers reaching out to touch the nape of his neck as if seeking assurance, the softness in her gaze whenever she looked his way — it wasn’t mere camaraderie. It was deeper, more profound. Something about it gnawed at Shigaraki, carving a hole in his heart.

It was in the details, the minute, almost imperceptible things that he began to notice. Momo's body language, the softness in her voice when she spoke to Mokami, the trusting glance they shared. Shigaraki's mind reeled as the realization hit him like a physical blow.

They were romantically involved.

A cold, hollow feeling settled in his chest as he recalled the moment he had declared his love to Momo. Her response had been a look of disgust, a rejection so swift and complete that it still stung. She had told him that her heart was already claimed, and he had assumed it was some insignificant crush, something she would outgrow, something he could remove.

But it was Mokami.

Mokami, who stood there with a serene expression, his eyes never betraying any emotion, yet in them, Shigaraki saw the same love mirrored back at Momo. A connection that went deeper than mere friendship or even their shared experiences of growing up together. A connection that Shigaraki realized he could never break or replace.

Why? The question tormented him, twisting in his mind like a knife. Was he so unlovable, or was Mokami just too perfect? Why did Momo choose Mokami?

He could see them now, the two of them together, their unspoken understanding, their shared glances and subtle touches. It was all there, plain as day, and Shigaraki felt a bitterness rise within him, a resentment that threatened to consume him.

"Mokami," he spat, his voice dripping with venom. "Why her? Why do you get everything? What makes you so special?"

Mokami's eyes met Shigaraki's, his expression unreadable, his silence unbroken. He didn't need to say anything; his very presence was a powerful response.

The battle raged on around them, but in that moment, it was as if time had stopped. The air was thick with tension, the complex web of emotions, love, jealousy, hatred, all laid bare.

Shigaraki's hands clenched into fists, his nails digging into his palms. The rejection, the realization, the unfairness of it all—it was too much.

Mokami watched him, his eyes never wavering, his stance resolute. He was the calm in the storm, the unmovable force that Shigaraki could not break.

The silence stretched, heavy and oppressive, until finally, Shigaraki turned away, his face contorted with rage and despair.

He had lost. Not just the battle, but something far more profound. He had lost to Mokami in every way that mattered, and the wound was one that would never heal.

In the end, he was left with nothing but the haunting question that would plague him for the rest of his life:

Why?