The Reason

"Uh... What happened here?" As Shirai Kuroko glanced around and saw the street completely destroyed beyond use, she felt a headache coming on and looked rather aggrieved. "Ah, there goes my vacation. Ah, the time with Onee-sama is gone..."

"Ahhhh! Isn't Academy City supposed to be the safest city in the world? Why are there so many violent attacks lately!" Kuroko tugged on her twin tails in frustration. It's one thing if it happens in other districts, but why is it always the Seventh District, where she works?

Ignoring Kuroko's ranting, Misaka Mikoto surveyed the surrounding ruins with a serious expression, feeling a bit shocked. From the damage at the scene, none of it appeared to be caused by energy attacks.

On the contrary, it all seemed like physical destruction. Except for the clean cuts from sharp tools, most of the damage was in the form of spiderweb-like cracked pits.

"It must have been caused by two people, and it's certain they were fighting. But who could cause such strong destruction?" Mikoto had some guesses, but no leads. Academy City does have Level 5 espers with strong physical abilities, but could it be him?

Soon after, Anti-Skill officers arrived and sealed off the entire area. They were having a tough night, running between locations and handling major incidents causing massive property damage.

...

JonaGardeN Restaurant.

Thanks to Selene's intervention, Mikoto's lightning attack didn't go off. Although her previous two attacks caused some damage to the power hub, the impact wasn't severe. Unlike in the original story, repairs were completed in a day, restoring power.

It was the same restaurant as last time, but they booked a private room this time. Selene had no choice, as having five people together seemed odd.

Selene appeared relaxed, while Kamijou Touma and Kanzaki Kaori looked serious, Stiyl was impatient, and Index was reluctantly present. Perhaps the atmosphere was indeed a bit strange, so the waiter quickly left after Selene ordered.

Turning her gaze to Selene, Kanzaki felt very complicated inside. So, she didn't use her full strength against me.

In the end, it was Kamijou Touma who couldn't hold back and spoke first. He had no choice; his credit card was busted, and his house was gone, meaning he had no money! "Uh... Why did we come to a restaurant... Also, I'm out of money!"

"Alright, alright, I'll cover you... Hm? Why are you all looking at me like that? Uh... Fine, you're outsiders and have no money, I'll cover you too." Upon hearing Selene say she'd cover Kamijou's expenses, everyone else turned to look at her, making her feel a bit overwhelmed. She sighed and agreed.

"Okay, let's get back to business and discuss the main issue. Since you claim not to have any intentions toward the contents of Index's mind and call yourselves her friends, why are you still chasing her relentlessly and even injuring her?"

Index listened to Selene with a look of confusion and doubt, but when she saw Stiyl and Kanzaki, she instinctively tried to hide.

"To protect her..." Kanzaki's face showed struggle, but she explained the reason. "When she ran away, she attracted a lot of attention. We acted this way to protect her from being captured by those with evil intentions."

"Lies, you were clearly trying to kill me!" Index was incredulous upon hearing this.

Index's open dislike and hatred pierced the defenses of the two mages, leaving them with pained expressions.

"Then why use this method of protection?" Kamijou couldn't help but ask.

"Over 85% of her brain capacity is occupied by the 103,000 grimoires in the Index Librorum Prohibitorum. She can barely function using the remaining 15%..." Kanzaki said with her head lowered and eyes closed. "She can only use 15% of her brain capacity like an ordinary person, and she has [Perfect Memory]. If she keeps remembering like a normal person, her brain will soon be overwhelmed..."

"If we don't erase her memories, she'll die..."

"So you have to erase her memories every year as her friends, even if it's against your will, even if she'll forget and even hate you?" Selene said, not judging them, as their intentions were good within their limited perspective. She didn't know Index well and had no reason to criticize them from a moral high ground, as someone else would surely step up.

"Do you really want Index to live in a fake paradise? A life without memories is hell in my eyes! Isn't this result just what you want?" Of course, Kamijou, filled with righteous energy, jumped out to criticize Stiyl and Kanzaki.

Luckily, he had the means to solve this issue.

"Bastard!" Stiyl was agitated, his shoulders trembling as he spoke through gritted teeth. "What do you know? Watching her lose her memory again and again, do you think it doesn't affect us? Don't you think we've tried? But nothing works!"

"You've only used methods from the magical side, right? Haven't you read any popular science books?"

Hearing this, Kanzaki responded, though puzzled by Selene's question, "No, is there a connection?"

Upon hearing this, Selene couldn't help but sigh, "In March 2014, an article in Nature analyzed the structure of 71 million neurons in a mouse brain, requiring up to 1TB of data. A human brain, weighing about 1.4 kilograms, has about 86 billion neurons."

"Huh?" Kanzaki was confused. "What does that mean?"

"It means, by simple calculation, a person's brain storage capacity is equivalent to 10,000 libraries, each holding 10 million books."

Kanzaki and Stiyl's eyes widened as they stared at Selene. If there was another way, why had they gone through so much trouble? "Wait! You mean... Index's brain won't be overloaded?"

Smiling, Selene said calmly, "That's right. In other words, how many years back can you remember?"

"Around ten years."

"So, you can remember ten years of things? Your memory can store ten times as much as Index's for a year, which is ten times 15%, or 1.5 times a normal person's. So why isn't your memory overloaded?"

Shivering, Kanzaki and Stiyl were horrified by their thoughts. If this were true, what had they been doing all these years?

"The human brain will never be overloaded by such information. A normal human brain can store memories for 140 years. Besides, the brain categorizes memories differently and selectively forgets unimportant things. In terms of brain science, no amount of knowledge will compress memory," Selene continued.

"And more importantly..." Selene suddenly crossed her fingers on the table, pressing her lips against her left index finger as she thought. "There's a foreign object in her throat."

"What? ×4" The four others were bewildered.

"I believe you know more about this than I do. You can take Index to the bathroom and check for yourselves. Seeing is believing; you can judge for yourselves," Selene suggested, pointing at Index's throat.

Kamijou and Stiyl agreed, and Index, understanding the situation, didn't resist. Kanzaki took Index to the bathroom.

A few minutes later, Kanzaki and Index returned with dark expressions. "It is indeed the Church's magic..."

Faced with this harsh reality, Stiyl extinguished his cigarette, his expression grave, unsure of what to do. This meant he had been deceived by the higher-ups, causing unnecessary harm to Index all along.

"...How could this be?" Kanzaki's face showed regret and sorrow, her eyes moist. "Then what have we been doing to this child..."

"Who told you her memory is only 15%, and that she'll die if her memory is overloaded?"

"The leader of the Church of England..."

"There you go. Everything you've been through is caused by the Anglican Church." This statement was directed at the stunned Index.

Selene continued speaking to Kanzaki and Stiyl: "To put it another way, in a more malicious speculation, even if her memory is really only 15%, doesn't the magical side have memory-related spells? Why not teach her so she can manage her memory better?"

"Or maybe the thing in her throat is some trick by the Anglican Church, and its purpose is to control Index, the Index Librorum Prohibitorum. Perhaps the annual memory wipe is to make this control effective."

"That's impossible... Why didn't the higher-ups tell me any of this..." The conspiracy theory overwhelmed Stiyl, his eyes widening as he struggled to accept the reality.

"It depends on what the Church's higher-ups think... In Academy City, these popular science books are everywhere. You can check them yourself. That's all I have to say. The rest is up to you."

After speaking, Selene ignored the two of them. Coincidentally, the restaurant began serving food, and Selene prepared to enjoy her meal.

...

The meal ended, and except for Selene and Index, who enjoyed themselves, the other three seemed distracted.

After settling the bill and exchanging phone numbers, Selene teleported away.

After all, Selene had thoroughly exercised today, and she just wanted to go home and soak in a bath.

With Selene's departure, Kanzaki and Stiyl exchanged glances and left silently, as they had much to investigate.

Soon, only Kamijou and Index remained. Noticing Index grabbing his shirt, looking at him with stars in her eyes, Kamijou felt helpless. Rubbing his head bitterly, he said, "I don't even have a home now; I guess I'll have to crash at Miss Komoe's place..."