A great number of boys and girls flooded into the air conditioned store.
The chain of used bookstores it belonged to advertised the fact that its prices were cheap and that reading things in the store was okay. Most of the people in the store were there because they wanted to read a certain manga but not enough to buy it.
"…"
Kamijou stood blankly amid it all.
There was indeed a book called "How to Raise Cats" on the bookshelf in front of him. The spine of the book was faded and it was cheaper because of it, so he had no complaints there.
But Kamijou couldn't get over the fact that a book titled "How to Cook Delicious Beef" was in the shelf right next to "How to Raise Cats".
"…Well, it is true that both books are about animals I guess."
When he moved his gaze even further to the side he spotted a book called "New! The Scientific Cows of the Farm Buildings".
There were a few buildings in Academy City that had no windows. They were referred to as agriculture buildings and were used to grow hydroponic vegetables and raise animals for meat.
Inside the buildings were vegetables that were bathed in ultraviolet light, breathed carbon dioxide that had been through air purifiers, and spread their roots in water that had all sorts of nutrients mixed in. Apparently people from outside of Academy City found all that to be "creepy". They seemed to think eating things that were created scientifically was bad for you.
(…It's the opposite. How can you eat vegetables that were grown in dirt that could have had industrial waste and who knows what else mixed in?)
That difference in values was one of the walls between those within Academy City and those without, but Kamijou simply pulled "How to Raise Cats" from the shelf without thinking on it any further.
A girl ran through an alley that ran behind the used book store.
One of her shoes came off.
The girl felt that running with only one shoe would be difficult, so she pulled off the other one and continued to run.
With her shoulder-length brown hair, short-sleeved white blouse, summer sweater, and pleated skirt, she reminded one of a Tokiwadai Middle School student at first glance. And someone more familiar with a certain Tokiwadai student would be reminded of the name Misaka Mikoto.
However, there were two things that did not match the title of middle school student.
The first was the military goggles on her forehead.
The second was the assault rifle she held in her right hand.
The assault rifle was made of laminated plastic instead of steel. As it was shaped in a functional aesthetic type of way like something one would see on a fighter aircraft, it looked like a toy gun from some kind of SF world. And that appearance was not necessarily wrong.
The rifle, the F2000R Toy Soldier, detected the target with infrared rays and used electronic control to adjust the trajectory in real time to give the bullet the best odds of hitting. The shooter did not have to think about the wind direction or the expected evasion patterns of the target. If one aimed the barrel the way the "thinking machine" told them to, anyone could become an expert marksman. On top of that, it had special rubber wrapped around it to absorb shock and used carbon dioxide to reduce the recoil from firing as much as possible. While the Metal Eater antitank rifle was a monster that only a large adult could wield, the F2000R with its low recoil that was said to not even crack an egg was also a monster in that it could easily be wielded by a 2nd grader.
However, the girl had no way of dealing with her current situation even with that monster in hand.
Her raging pulse, exceedingly irregular breathing, and flickering, chaotic thoughts all clearly showed that she was the one being hunted.
A form approached from behind.
A white boy was heading for her from not even 10 meters away.
"Ha ha! What's with those fleeing hips? Why are you shaking your ass like that!? You're just asking for it!!"
That narrow alley was straight and lacking any kind of cover to avoid a bullet with, yet the unarmed "hunter" was overflowing with crazed passion.
Without stopping her flight, the girl twisted her body around to look behind her.
She aimed the barrel of the F2000R at the white boy named Accelerator who seemed to freeze the summer heat.
She did not hesitate to pull the trigger.
The rifle silently absorbed both the shock and the sound of the gunshot, so only the tiniest of an explosive noise left the barrel as if only a cheap firecracker had been set off. Nevertheless, 5.56 mm bullets accurately shot toward the boy's vital points.
Or so she had thought.
"...!?"
The girl's body froze due to shock. The 5.56 mm bullets held the destructive force to fly out the other side if they were shot into the side of a car, but they were repelled in every direction the instant they hit the boy's body. It was as if she had fired a cheap handgun at the front of a tank.
With the sound of flesh being crushed, a red hole had been opened in the girl's right shoulder.
One of the repelled bullet had pierced her shoulder.
"…E…Gh!"
The girl staggered. She immediately reached for the wall, but her legs got tangled together and her head struck the dirty wall. From there, she slid down to the ground.
"C'mon, how about a riddle to kill some time? Here's your question: What is it that the power of Accelerator does!?"
The girl heard a crazed laugh. When she looked up, she saw the boy's leg coming down with all his weight behind it to crush her skull.
"!"
She immediately rolled along the dirty ground and evaded the downward swinging foot. She then held the F2000R up and pulled the trigger.
She fired at what could almost be called pointblank range. The bullet seemed to be absorbed in toward the white boy's eye, but the instant it touched his soft eyeball, it was repelled to the side.
The white boy did not even blink.
His expression changed to a smile that made his dirty-white face look hideously burned.
He swung up his white hand. He swung up that hand that had an unknown effect.
"…!"
The girl immediately threw the F2000R at the boy's face as the rifle was now empty. She did not think that it would act as a fatal blow, but she hoped it would provide an instantaneous opening she could use to escape.
However, the boy did not move even slightly. The instant the rifle struck the boy's face, the F2000R broke to pieces. It was as if the gun had been chomped on by giant invisible fangs.
The girl did not have time to be frozen in shock. She twisted her body and managed to roll a step away from the boy. She swung around her left hand as she could still move that one and gathered power there.
She released a lightning spear from it.
The spear of purple electricity moved forward at the speed of light and held enough destructive force to knock someone unconscious.
She did not think that it would act as a fatal blow.
As long as it distracted him long enough for her to get away, that was enough.
However, the lightning spear she had fired at the boy rebounded and struck her in her own chest.
"Gah…!?"
The girl was knocked back to the ground with a shock that felt like she had been struck in the chest with a hammer. Her breathing stopped and every muscle in her body moved irregularly.
The girl's trembling lips managed to put together a single word.
"Re…flection…!?"
"Sorry, that's not entirely wrong, but it still doesn't get to the essence of what I can do!"
The girl somehow tried to distance herself from the boy, but her body would not do what she told it to due to the electrical attack she herself had fired.
"The answer is vector transformation! Motion, heat, electricity. I can alter any kind of vector that touches my skin. I have it set to reflect by default, though!"
The girl looked up at the boy's face in shock.
The 2.3 million espers in Academy City were indeed special humans, but not many of them could defeat even a handgun with their power. And if they could defeat a handgun, you would use a machine gun. If they could defeat a machine gun, you would use a tank, a fighter aircraft, a battleship with submarines, or as a last resort, even a nuclear missile.
There were no espers who could defeat something like that. In fact, it would just be a lot easier to buy a handgun rather than controlling the brain and altering the arrangement of genes in order to create a power that could fight against a gun. It just seemed absurd to create a huge psychic powers development institution that slipped past international law in order to create something on the level of a cheap weapon that could be bought in American supermarkets for about 30,000 yen.
That was why Academy City's goal was not to create espers. The espers were nothing more than a type of litmus paper. It seemed what was truly important was why espers had been born and what mechanism brought them about.
Yet the boy before her eyes was different.
That boy could alter all vectors be they motion, heat, or electricity, so he would not be injured even if he were directly hit by that last resort of a nuclear missile. He would just reflect the shockwave that would blow everything way, the heat that would scorch everything, and the neutrons and radiation that would kill everything.
He was Accelerator, Academy City's strongest Level 5.
The word "monster" came to the girl's mind. The creature before her eyes that had a human form held the power to singlehandedly make an enemy of the entire world and survive.
The boy crouched down next to the girl.
"My Level 5 power lets me control every kind of vector." That boy seemed so different, but he spoke as if it was nothing. "If I use it, I can even do this."
The boy stuck his slender index finger into the dark-red hole in the girl's right shoulder. It was like the action of a child squashing a bug on the road.
"…!!"
There was a sound like a red fruit being squished and the girl's body stiffened in intense pain.
"Now, it's time for the question for the consolation round," Accelerator said mockingly. "I'm touching your blood. I'm touching the flow of your blood. Now, if I reverse that vector…If I reverse the vector of your blood, what will happen to your body? A correct answer gets you a nice peaceful sleep!"
A blank expression appeared on the girl's face as if she did not understand what was going on.
An instant later, unimaginable pain assaulted her entire body.
"Huh?" Kamijou said upon leaving the used bookstore with a paper bag in one hand.
Misaka Imouto was nowhere to be found.
(Maybe she got mad that I forced her to take the cat, so she left.)
The cat alone was sitting there on the ground.
Kamijou picked up the cat as it laid its ears back and trembled a bit. He looked around the area again, but everything about the street tinted in the colors of twilight seemed normal. A lot of boys and girls wearing private clothes were walking along the street as they returned to their dorms after an exhausting day of fun.
(…?)
As Kamijou casually looked around, he felt something from that normal scenery. He spun back around and looked at the alley between the used book store and the multi-tenant building next to it. Something about it drew his attention.
(What is it? What's wrong with that alley?)
Kamijou looked closer. A tile walkway headed along in front of the entrance to the alley and a wind turbine spun nearby. The entrance must not have gotten cleaned often because quite a few leaves and a single girl's shoe were gathered there. The tiling of the pathway ended right at the alley entrance and the ground in the alley was made of incredibly makeshift-looking asphalt.
…A single girl's shoe?
"…?"
Still holding the black cat, Kamijou approached the entrance to the alley. A bad feeling crawled up within him like a centipede. There was definitely just one girl's shoe there. It was a small brown loafer that looked like something that would be required by a school. The shoe was clean and had no dirt on it, so it couldn't have been there for long.
Kamijou stared into the alley.
The sun was already sinking below the horizon, so its light did not reach the gap between the buildings. The darkness made it look like the entrance to a cave and he could not see anything within by just peering in.
"…"
Kamijou took one step into the alley.
With that one step, it felt as if the temperature had lowered 2 or 3 degrees. A feeling of having stepped into some unknown place slowly rose from his foot up to his body.
Kamijou continued on. There he found the other shoe lying on the dirty ground of the alley. He continued further on. The bad feeling grew. He tried to keep his pace slow, but his legs continued to accelerate. Kamijou didn't even know why he was hurrying, but his breathing and pulse were picking up pace as if they were falling down a hill.
Then Kamijou realized there were marks like part of the wall had been scraped off. It was as if someone had scraped along the concrete with a metal stake. And it was not just one or two marks. Both walls were covered with those marks like someone had been recklessly swinging a metal rod about.
Kamijou stepped on something.
It was a metal similar in color to gold…or more accurately, copper. It was a metal cylinder about the size of a battery. Kamijou thought it looked like the empty ammunition cartridges he had only ever seen in movies. There was a faint smell of smoke remaining as if someone had shot off a firework.
(What…?)
Kamijou almost spoke out subconsciously, but he suppressed it. For some reason, he tried to walk silently as he headed further in. With each step, he felt like the air was getting dirtier.
As he continued on, he saw something lying on the ground further ahead in the darkness. No, it was someone collapsed on the ground. He could see the legs from where he was. He could see two legs, but he could not see the upper half of the body as if it had been eaten by the darkness. Something was scattered around about the legs. It was plastic-looking shards and springs. It was almost like the remains of some sort of toy.
"Misaka…?"
Kamijou did not know why her name came out first. He headed closer as if he were cutting through the darkness obscuring his view.
And there she was.
Misaka Imouto's corpse was lying on the ground.