Brain Surgery Vectors

“Hey. If I can just control her brain’s electrical impulses, I can mess with her personality
data without having to use a Testament, right?”
“What are—” Yoshikawa began, then stopped and realized something.
A Testament was a device for installing a personality and knowledge base into a person
by controlling their brain’s electricity.
“...You want to be a replacement for a Testament? That’s impossible! You can freely
control any vectors with your ability, but manipulating someone’s brain signals is...Wait!”
“There’s nothing I can’t do. I killed people by reversing their blood flow and electric fields
just by touching their skin during that experiment, yeah? I can reflect stuff already, so it’s
not strange that I can go beyond and control it.”

***

He turned the reflection off on his hands, and his fingers touched the girl’s forehead. Her
skin was hot like she had caught a fever. He then found a bioelectric field and made
contact with its vector, like it was an antenna leading to her insides. He started to calculate
the vectors of the fields around it using the one he touched as a base.
Finally, the entire construction of the girl’s brain revealed itself to him.

***

His hands trembled.
He would use this power that could do nothing but kill in order to save someone. It was a
stunt as ridiculous as feeding a baby food using a spoon taped to a tank cannon.
“...That’s pretty funny. I’ll give you something to be scared of, sure,” he declared to himself.
He applied his power. He changed a vector. The battle began.
The virus would activate at 8:13. There were fifty-two seconds left until time ran out.

- Toaru Majutsu no Index Volume 5, Chapter 3 Part 8

Last Order’s indecipherable words began to change into Japanese. Sweat dripped from
Accelerator. He felt like something hot was burning the back of his head. He could see his
vision tunneling. As a result of him focusing all his calculation abilities to one place, his
reflection didn’t work, so his sweat clung to him unpleasantly.
He matched up Last Order’s personality data now that she was infected with the virus
with the preinfection personality data on the memory stick.
Any differences between the two would be due to infected code. Included in that were
memories of Accelerator from after the virus, but he couldn’t at all tell which parts were
the virus and which were memory.
The number of lines of code he needed to rewrite came to him.

In all, 357,081.
The only thing to do was to delete all the code to get rid of the virus.
The monitor showing Last Order’s vital signs continued displaying warning windows at a
terrifying pace.

- Toaru Majutsu no Index Volume 5, Chapter 3 Part 9