All Might's office was a mausoleum to victory. Golden trophies shone on mahogany shelves, silent testaments to a peace forged by fists. The air smelled of old leather and the solemn quiet that follows a confession.
Izuku entered first, followed closely by Ochako, Momo, and Toru. They sat on a sofa that seemed too large, too formal. Ochako wrung her hands in her lap. Toru, for once, wasn't making jokes. Momo maintained a posture of perfect stillness, but her gray eyes never stopped moving, scanning every shadow as if expecting an ambush.
The door opened without a knock. Nemuri Kayama entered with a confidence that didn't belong in that place. She wasn't wearing her hero costume, but an elegant business suit that made her look more like a lethal lawyer than a teacher. She closed the door behind her with a soft but final click.
Behind the enormous desk, Toshinori Yagi, in his skeletal form, stood up. The surprise on his gaunt face was genuine upon seeing them.
"Girls... Nemuri. The call was just for Young Midoriya."
"A bad call, Toshi," Nemuri replied, her voice calm but with a steel edge. "Nezu agreed with me. If you're going to drop a bombshell like this, everyone who's going to feel the blast radius had better be in the same room."
She crossed the room and stood beside the sofa, a silent guardian for the team.
Toshinori looked at her, and something in his posture deflated. He sighed, a king abdicating his facade, and collapsed back into his chair.
"I suppose you're right. My apologies. It's just... what I saw in class today frightened me." His gaze, now that of a tired man, settled on Izuku. "That speed, that control... Your Quirk is evolving at a pace that defies all logic. I once told you I believed in your Quirk's potential, Young Midoriya. I think I underestimated you. Not only do you have great potential, but the very nature of your power... it's what frightens me and gives me hope at the same time."
He poured himself a cup of tea, his hands visibly shaking.
"I am here because my time is running out, I have no successor, and you all have just painted the biggest target in all of Japan on your backs. You need to understand what we're truly fighting against."
The girls leaned forward, their faces a mixture of concern and an almost feverish curiosity.
"To understand my power, One For All, you first have to understand its opposite. You have to understand the man who unintentionally created it."
All Might looked out the window, his eyes lost in a past that was not his own.
"A long, long time ago, when Quirks first appeared, the world wasn't like it is now. It was hell. Society was crumbling, chaos was the only law. And from that chaos, a man emerged. A man with the power to steal the Quirks of others and make them his own."
Ochako stifled a gasp, clapping a hand over her mouth.
"He can do that...?" she whispered.
"Yes. And he couldn't just steal them. He could also grant them," Toshinori continued, his voice a low rumble. "He became a king in the shadows, unifying people under his power. But the Quirks he granted were often too much for their new owners. They left them in catatonic states, their bodies broken by a power they couldn't control... much like those Nomu you saw."
"So, those creatures at the USJ..." Ochako's voice was a trembling thread. "They were his pawns. People whose bodies and minds he shattered."
"It's his method," Nemuri confirmed, her face grim. "Turning people into puppets, into disposable weapons. It always has been."
"His name has been lost to history, but his power had a name. One that defined him perfectly: All For One."
The name settled into the silence, charged with an ancient malevolence.
"This man, this symbol of evil, had a younger brother," Toshinori went on. "A small, seemingly frail man. Everyone, including his brother, believed he had no Quirk. All For One, in an act he considered one of mercy, or perhaps control, decided to force a power onto him. A Quirk that could store power within itself."
All Might fixed his gaze on Izuku.
"But the younger brother wasn't what everyone thought. He wasn't an empty vessel. He did have a Quirk. One the world considered useless. An ability that was no good for fighting. His only power... was to transfer his own Quirk to someone else. A power that only served to be given away."
Izuku felt the impact of those words in his chest. A power that only served to be given away.
"The power-stockpiling Quirk his brother forced on him merged with his latent ability to transfer," Toshinori explained. "And from that impossible union, something new was born. A unique power. The ability to cultivate and accumulate the user's strength... and then pass that torch, with all its accumulated flame, to the next generation. The power of one for all. One For All."
Toshinori smiled, a sad, ironic smile.
"It is the universe's cruelest irony. The greatest power for good was born from a tyrant's act of trying to control his brother."
Izuku nodded slowly, his mind struggling to process the immensity of the revelation.
"I understand... I understand the origin. But why are you telling us this now? Why talk about a villain from so long ago?"
Toshinori's smile vanished.
"Because he never left. We believe All For One found a way to steal a Quirk that granted him an abnormally long life. A form of immortality." He lifted his shirt, revealing the horrific scar that ravaged his torso. "The man who did this to me, the one leading the League of Villains from the shadows, is him. I fought him and won... but it cost me almost everything. And I thought I had killed him."
He looked at Izuku, and the weight in his gaze was that of a testament.
"I have spent the last few years searching for an heir to One For All. Someone Quirkless, a worthy, empty vessel to whom I could pass this torch before my flame is extinguished completely." His gaze turned bitter, frustrated. "And then you appeared. I found the perfect spirit to inherit this burden... in a boy I cannot give it to."
The confession landed like a gravestone.
"Your heart, your strategic mind, the way you inspire loyalty..." All Might continued. "You are everything a wielder should be. But you already have a Quirk. Transferring One For All to you would kill you. It's like trying to fill a glass that's already overflowing. It would destroy you from the inside out."
"And that's where you all come in," Nemuri intervened, her voice drawing the girls' attention. "With no successor, with All Might weakening, and with All For One moving in the shadows... who do you think is now the greatest threat to his plans? And the greatest prize?"
Momo, Ochako, and Toru looked at each other, the realization dawning on them with terrifying force. They were no longer just promising students. They were the world's unofficial Plan B.
"It is very likely, Young Midoriya," Toshinori concluded, "that one day, your path and his will cross. And you will not be alone, but the responsibility... the weight of stopping him... could end up falling on your shoulders. On all of your shoulders."
The silence that followed was absolute. The true scale of the threat, the true enemy, had just been revealed. Izuku looked at Ochako beside him. He saw her pale face, but in her eyes, there was no fear, only a fierce determination. He looked at Momo, who was nodding slowly, her mind already calculating odds and countermeasures. He looked at Toru, who had stopped trembling and now had her fists clenched. He looked at Nemuri, whose expression was that of a warrior who had just received her battle orders.
Then, he turned back to All Might.
"I won't face him alone," Izuku said, his voice quiet but unbreakable. "You didn't ask me to replace you. You asked me to stand by your side. We will face him... together."
The word "together" became charged with a force that seemed to fill the room with light. All Might looked at him, and for the first time in a long time, he saw a spark of pure hope in a future that didn't depend solely on him. He wanted to tell him that he probably wouldn't be by his side when that moment came, that his time was running out. But he couldn't. Instead, he smiled.
"Thank you, Team Midoriya."
The next day, the forced normality of class was almost comical. Shota Aizawa, with his usual air of exhaustion, slid up to the podium.
"Alright. Listen up. During summer vacation, we'll be holding a training camp at a forest lodge."
A murmur of excitement rippled through the class.
"However," Aizawa continued, a malicious smile creeping onto his lips, "any of you who fail the final exams that start next week... will be staying here at school for a hell of remedial classes."
The euphoria turned to instant panic.
"WHAT?!" Kaminari yelled.
"A challenge! How manly!" Kirishima exclaimed.
Bakugo just smirked.
"More extras to crush."
Izuku's team exchanged a look. The exams were now just the first hurdle on a much longer, darker path.
Elsewhere, in a dark room lit only by medical monitors, a man with no visible face watched the news.
"Stain's capture... what a surprise," All For One's voice said, calm and amused. "But, in the end, it's all going according to plan. His ideology is spreading. It's attracting the disgruntled, the broken. He's the perfect bait."
Beside him, a man in a doctor's coat and thick glasses nodded.
"Is young Tomura ready, Sensei?"
"His task will be to oversee and unify the new recruits that Stain's fame will attract," All For One replied. "I will let Tomura do all the hard work. Let him get his hands dirty. He was born for this. To become my successor."
A cruel smile was hinted at in the darkness.
"Enjoy this fleeting peace while you can, All Might. Because the real storm... is about to begin."