Chapter I
Accelerator

Misaka Mikoto was scared.

In front of her, there was an idiot. An idiot who despite had a strange power to negate her attack, didn't use it to defend himself.

Yet, that idiot also gave him hope. Hope that maybe, there were other people who cared about her problem without calling her a monster for willingly gave her DNA to those researchers.

Misaka Mikoto stroked the idiot's head.

When he opened his eyes, Kamijou Touma didn't expect to wake up in her lap. Nonetheless, he tried to move his body, but found himself unable to do it.

"Why?"

A single word escaped Misaka Mikoto's lips. It was spoken with such emotions, that Kamijou could hear the sobs that ready to burst from her.

"Thank goodness."

Kamijou smiled.

"…How can you smile like that?"

Tears ran down to Kamijou's cheek. It was confirmed. Misaka Mikoto was crying.

"Because I'm glad to be your friend, I want to help you. So, please stop crying."

But those words didn't stop the tears. Misaka Mikoto was, after all, still a teenager, not that he didn't. But as a teenager who was involved with such cruel experiment, he expected she would cry.

After several try, Kamijou finally could stand. "I've figured it out. I've figured how to stop the experiment."

Misaka Mikoto didn't say anything. She was still trying to stop those tears from falling.

"The experiment took the fact that Accelerator was the strongest esper. If you think about it, the way to stop it was simple. Just make sure that Accelerator is not the strongest. All you need to do is make him looks absurdly weak."

"That's not possible," replied Mikoto. "I'm a Level 5 like him, and he's on the other whole level than me."

Kamijou didn't say anything. She was right. Kamijou didn't know how strong Accelerator is supposed to be. "If the words that Accelerator was defeated by a mere Level 0, what do you think?"

Mikoto widened his eyes. "Don't be stupid! There's no way a Level 0 like you could beat him! He is the kind of person who would only laugh if the whole world's army is after him!"

Kamijou didn't respond.

"He has the power to control any vectors as long as they are touching his skin! An overpowered ability like that doesn't have any openings you can use! All of his attacks will reach you, but none of yours will reach him! It's unfair! In fact, everything you can throw him will reflect back at you!"

Kamijou clenched his right fist. The existence that is Accelerator, supposed to be the strongest.

"Please… you can't defeat a monster like that!"

But with power that known as Imagine Breaker within his right hand, could he defeat him?

He didn't know the answers.

So he took a step forward.

"Misaka, you said you were about to go to where Accelerator is right?"

After all…

"Then tell me, Misaka. Where is he about to start the experiment?"

After all… you won't know anything before you try it.

Misaka Mikoto's eyes were red from crying.

"I couldn't stop him…"

Even though she was supposed to stop anyone from dying because of her, she couldn't stop him.

She was pathetic.

She was supposed to be the Railgun, the third strongest esper in Academy City. But she can't even stop a single boy from his suicide in the form of helping her.

She was supposed to stop the experiment alone, where she would sacrifice herself to stop Accelerator. But all of those thoughts were useless.

A single idiot boy stopped it all.

"'Because he is my friend', he said."

The single boy was on his way to help her.

"Well, if that's so, I don't want him to die by Accelerator, because he is my friend."

Misaka Mikoto found her resolve.

With a steeled heart, she decided to follow the idiot.

When Kamijou Touma decided to face Accelerator alone, he expected Accelerator to laugh, or mock him. After all, that's what he would do if he had power like Accelerator and then someone without power challenged him.

But instead of that, what greeted him was a shocked face of the strongest esper.

"Kamijou, what are you doing here?!"

Eh? He knew him? The Accelerator knew a Level 0 like him?

What's next? Both of them were childhood friends? Haha, as if something like that happened.

"Accelerator! I'm here to stop you!"

Kamijou said this with a stone face.

"Hm? You never called me Accelerator, so it was a little strange. Anyway, stop me? What do you mean?"

As he expected, someone who hold the title of the strongest esper would mock him.

"I said I will stop you! Killing those innocent sisters without remorse… you are a monster!"

Accelerator's red menacing eyes widened. Meanwhile, MISAKA 10032, dubbed MISAKA Imouto by Kamijou was lying under Accelerator's feet. Her body was full of bruise, there was a blood on her blank face.

"'Why… are you here…?' asked MISAKA."

"I will save you, so please, don't throw your life like that! Misaka was crying, you know. She cried because she thought she was the one who sent you to your death. So please, don't throw your life like that!"

"'You…' said MISAKA as she tried to move her body."

"Monster you say…" Accelerator's face was covered by his bangs, giving him an even scarier looks. "If only you were there, I wouldn't accept this experiment at all!"

"Eh?"

That was the only words that found its way from Kamijou's mouth. If only he was there?

"That's right, after your father took you to Academy City, some researchers found me, and took me to Academy City too, leaving Hamazura all alone. I know it was wrong decision, but I was hoping by coming to Academy City, I could find you. Everything was just not the same without you there, Kamijou."

Nearing the end of the speech, his tone changed from angry into sad. Reflecting how his heart was feeling.

"But all those researchers always made me went through all kinds of experiment regarding my strange power, and after countless experiment, they got that my power is controlling all kinds of vector, I call it Accelerator. I tried to find you, but I can't. The situation at that time was just like before I met you, everyone can't touch me. Then, Kihara Amata found me, he trained me in the way that all those researchers could never do. I became the number one!"

He moved towards Kamijou, leaving MISAKA Imouto's body behind. Despite his overwhelming presence, Kamijou didn't take even one step back. He remained in his position.

It's not that he did not fear Accelerator, he did fear of Accelerator. But right now, Accelerator was revealing a bit of his past, which connected to Kamijou's own past as well. So he patiently listened.

"What do you think I feel back then? All I want to do is find you and tell you how I became the strongest. But again, I couldn't find you. Sometimes later, some researchers sought me. They said I could become the first one to be Level 6. In order to do that, I have to kill 20000 clone of Railgun. I was scared! I was scared because in order to gain more power, I need to kill! What I want to do was found you and then asked your opinion, but I never found you!"

Accelerator and Kamijou stood, facing each other with only three meters distance.

"It's all because of you! If you were there, I wouldn't choose this! And now you had the gall to stop me? HA! You lost the right to stop me when you never contact me in the first place."

Calmly, Kamijou responded, "Are you done, Accelerator?"

"'Are you done?' you said, all this years you never contacted me, and what you say was just 'Are you done?" Accelerator clenched his fist. "Don't fuck with me!"

A sound of glass breaking could be heard. Accelerator's palm meet Kamijou's fist.

"Oh yeah, forgot that you never affected by my power. Even Hamazura was affected."

So Accelerator knew Imagine Breaker as well? Damn, his only weapon was already known to Accelerator.

"Ah, please call me by my name. Hearing you call me Accelerator is kinda funny."

Ahahaha, he was joking right?

Kamijou had amnesia, or rather, his brain cell was destroyed. So he didn't know Accelerator's name, or rather, his memories where he knew Accelerator's name was gone.

"What's the matter? You forgot it?"

"…yeah," was the lame reply that Kamijou could uttered.

"The fuck? You forgot your own childhood friend name?"

"Yeah…"

"Hold it right there! Accelerator! You won't be able to kill any more of my sisters!"

It was at this scene that Misaka Mikoto entered. She imagined that Accelerator would stand before Kamijou's body. Or Kamijou barely stand with his body full of bruise in the opposite the monster who only laugh at Kamijou's weak attempt to fight him.

She never imagined that Accelerator and Kamijou stood in front of each other without bruise, and just talking.

Both of them stared at her. From behind them, she could feel the stare of her sister too.

"What? What happened?"

After the initial shock that ran through Mikoto's body, she demanded to know what happened, why Kamijou didn't try to defeat Accelerator, even though it was impossible.

"So, let me get this straight. You and Accelerator are childhood friend, and this experiment was happened because Accelerator couldn't find you and asked for your help?"

"Err, apparently so. I myself still couldn't believe it."

"Yes, it was because of you. Now, I would like to ask something Kamijou. There was no way you could forget my name, you said it yourself. So why the hell can't you say my name? We haven't meet in a long time and the first time we meet you greeted me with shouting and calling me Accelerator. It's like you have amnesia… you have, haven't you?"

Sweat ran down from Kamijou's temple. His secret couldn't simply discovered with just a guess could it?

"Heh, knowing your luck, it would happen anyway. How long did you have amnesia?"

"Er, who said anything about amnesia?"

Accelerator stared at Kamijou. "You can't fool me. You never succeeded in fooling me before, so I know it when you lie. Just blurt it out. I won't angry at you or whatever, just tell me."

Kamijou stared back at the one known as Accelerator.

"Hold it. Amnesia? Is it true?"

Kamijou lowered his head. "I guess the cat is out of the bag."

"Ha, like I said you can't fool me."

"Anyway, what should we do about this experiment?"

"Oh yeah, you are here to stop me huh? I think I know a way to stop this experiment. Easy, just make them think that I am not the strongest."

"We had the same thought."

"Of course, we were best friend back then."

Misaka Mikoto could only stare at both men. She can't even force her way to their conversation. It's like the conversation between close friends, that some outsiders couldn't enter.

"'Onee-sama….' Said MISAKA as she too couldn't understand what just happened."

"No, it's not like that. I understand, it's just that those two were like destined to be friend, that even if the idiot was amnesiac, they still could carry this conversation."

"'MISAKA still couldn't understand, but somehow MISAKA get the picture,' said MISAKA as she nodded her head."

"The idiot was amnesiac! No wonder he acted strange when we met at the vending machine." Mikoto only realized that now. She should have seen the sign. How many times she told him her name? Two? Three? She forgot. But he still asked 'Who are you?' when they met at the vending machine.

So the idiot wasn't too idiot after all.

Meanwhile, Accelerator and Kamijou were still talking.

"So you and I had the same thought, let's settle this."

"No, I'll be defeated by you. Just one last punch, okay?"

"Uh, sure," Kamijou took a few step back, and then he faced Accelerator again.

"Accelerator, what do you mean by 'I'll be defeated'?"

"Huh? Oh yeah, you're here, Original."

"Grrrr, just tell me!"

"Sure. That Kamijou was never affected by my power before, what do you think will happen now? He still won't be affected by my power at all. One punch and then BANG, I'll be defeated. Now, stand aside. I'll let him beat me."

Kamijou ran towards Accelerator. Accelerator ran towards Kamijou.

Two existences holding unique power; One Level 5, and one Level 0, clashed.

Kamijou's fist met Accelerator's cheek. A sound of glass breaking could be heard, Imagine Breaker negating Accelerator.

Accelerator's body thrown a few meters backward.

Misaka Mikoto, who was watching, could not believe her eyes. What Accelerator said was true. When she used her signature move, the Railgun on him, it bounced back to her. Yet this idiot… with just his fist, he had managed to hurt Accelerator.

Unconsciously, she sighed.

It was over. With this, the Level 6 Shift project could be stopped entirely.

Misaka was not naïve. She knew, if somehow Accelerator wouldn't want to continue the Level 6 Shift project, maybe the Number Two Level 5 would be offered to do it again.

So the idiot's solution is the best way to stop the whole project. By making them think that Accelerator, the strongest esper, could be defeated by a mere Level 0, then that means that other esper below him could also be defeated, which would demoralize all the researchers.

Misaka Mikoto smiled.

A/N: So… how do you think? The first Accel vs Touma was always one of the best fight in Toaru series. Instead of battle, we have a unique reunion between them. Touma was already saved Index after all, and I don't want to change that. That's why I jumped into Sisters Arc.

OOC Accel? Of course. Touma already changed how Accel act. But we will see how much Touma changed Accelerator later. Oh, and Hamazura too, will act OOC later. But I don't want to make them too OOC, Accel will still has his colourful language, even though it's hard to wrote that. What can I say, Kami-yan disease's true horror was not attracting female attention, it was influencing someone. Look at Kamijou Faction. All of them were the one who's influenced by him.

Now that I think about it, should I change the rating to M? Accel's language was bad after all.

So, after I wrote this chapter, I kinda stuck. Where should I take this story to? What arc should I write after this? Well, I had thought about a different Three Stories Arc, but still haven't had the full image of how different should that be.

Tell me your thought, and sorry for the grammatical error, if anyone want to be a beta reader, PM me and we can discuss it.