When compared to traditional auxiliary equipment such as magic staves, tomes, or talismans, CADs possessed superior invocation speed, refinement, complexity, and were capable of executing large scale magics. They were the definitive auxiliary equipment in the modern age.

That being said, they weren't universally superior in all categories when compared to traditional auxiliary equipment. Due to the precise nature of CADs, when compared to traditional auxiliary equipment, maintenance required additional effort. For the best performance, the CAD's system had to be fine-tuned to the user's Psions, which were much like a painter's ink with the whole painting being the final magic. Depending on the quality of the CAD, the magic invocation speed could be influenced anywhere from fifty to one hundred percent.

In other words, Psions are particles of thought or consciousness made concrete. Their manifestation can be extremely diverse. For every user, there is a different type. As such, if a CAD wasn't tuned to a user's Psions, the user would encounter great difficulty in managing the exchange of Psions. There were also other points that go into customizing a CAD, all of which would fall under a Magic Artificer's purview. As such, exceptionally skilled Magic Artificers were seen as coveted treasures.

In addition, because Psions come from the mental and physical status of a person, they change and grow along with a person. In fact, small fluctuations naturally happen every day. While these daily fluctuations are not enough to gravely affect the CAD's compatibility, it was still ideal for the CAD to undergo maintenance daily.

However, as CAD maintenance equipment was generally extremely expensive, generally only the military, police, central government, first class research institutes, famous schools, and well-financed major corporations possessed the power and funding for CAD maintenance equipment and related trained personnel. The average Magician resorted to using a Magic Machine Customization store around once a month or a Mechanical Service store for scheduled check-ups. First High was considered to be one of the nation's premier schools, and consequently possessed special facilities for student use. It was not unusual to see students or faculty on campus undergoing CAD maintenance.

However, due to special circumstances, Tatsuya's house also contained state-of-the-art CAD maintenance equipment.

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After dinner, Tatsuya was in the basement, which had been converted into a CAD maintenance room for said maintenance equipment. Miyuki knocked on the door, and Tatsuya invited her in.

"Excuse me, Onii-sama," she said with a small bow of her head, "I was hoping you could adjust my CAD..." She looked up at him hopefully, fidgeting slightly in the simple white robe she wore that wouldn't have been out of place in a hospital.

"Are the settings incompatible?" Tatsuya asked, glancing at the cell-phone shaped CAD she held in her hands.

"That's impossible!" Miyuki cried, "You're adjustments are always perfect!"

The last time they had done a full maintenance was only three days ago. Since they normally only did a full maintenance once a week, Tatsuya thought she must have come to him with a problem.

"It's just that," continued Miyuki hesitantly, her voice trailing off.

"Go ahead," said Tatsuya, "There's no need to be shy."

Gathering her courage she said, "Sorry. I actually wanted your help to change a few Activation Sequences."

"Just that?" replied Tatsuya with a soft smile, "That's nothing to worry about. I was getting a little worried." He softly brushed her hair as he took the CAD from her hands. She dipped her head in embarrassment. "So, what systems did you want to add?" He asked.

General CADs were limited to 99 Activation Sequences. Even Miyuki's highly customized CAD could not surpass this limit.

The variability of Activation Sequences were dependent on where the Activation Sequence combination ended and where the individual's Magic Calculation Area began in terms of execution. In reality, there were unlimited combinations. Generally, however, targets, strength, and ending requirements were variables for the Magic Calculation Area, while all other essential requirements were incorporated into the Activation Sequence. Many Defense-type Magics relied on using the physical self as a fixed marker in relation to the target reducing the amount of variables, while Contact-type Magics quantified all the numbers. More fixed quantities written into the Activation Sequence lessened the amount of skill and calculation the Magician needed to perform, but also lowered the flexibility of the Magic's use.

Miyuki belonged to the minority that registered a wide variety of low fixed quantity, highly flexible Activation Sequences. For fifteen-year-old Miyuki, who could grasp magics beyond what her years would suggest, 99 types was far below her actual ability. She could switch around the combination of Sequences in her CAD in order to adapt to her changing preferences or situations.

"Ummm... Binding type sequences," Miyuki said finally, "I want to increase the types of Anti-Personnel Combat Magic."

Tatsuya furrowed his brows slightly, saying lightly, "You already have Speed-type Magics, so do you need to add Binding types as well?"

Miyuki specialized in Speed-type Magics, so it was only natural for her to have a majority of Sequences relating to Speed. Miyuki was especially good at Freezing Magic, a subset of Speed-type Magic, and her Psions manifested themselves this way when she lost control over them. Because of this and her abundance amount of Magic Power, Miyuki generally relied on relatively slow-to-cast, large-scale Freezing Magic, overwhelming her opponents with the sheer amount of her power.

"Onii-sama," Miyuki began, her voice gaining power as she explained, "As you should know, Speed Magic is rarely directed towards the user, and it is very difficult to work with. Partial freezing is practically impossible, and it's Invocation time is very long. After watching today's match, I realized I'm lacking in Magics with fast Invocation times with the intent on using minimal force to subdue my opponent."

Tatsuya pursed his lips in thought before answering carefully, "Using speed to attack before the opponent is ready is a legitimate strategy, but I don't think it suits you very well. Don't you think making good use of your superior Zone Interference skills far better?"

When an area or zone has been saturated with one user's magic, it has been effectively rendered "Unable to be Changed", and all attempts by an opponent to activate magic on their surroundings will be nullified. With her enormous power, Miyuki's Zone Interference was extremely superior.

However, at Tatsuya's words, Miyuki's face fell as she asked sadly, "So I can't do it?"

Faced with Miyuki's dejected look, Tatsuya stood no chance. "I guess it's alright," he sighed, "This strategy might be necessary against a fellow student while you are in the Student Council, I understand. I won't touch your core Sequences, but I will adjust the systems." Remembering a suggestion he had posed to her before, Tatsuya continued, "But, you won't consider getting another CAD?"

Miyuki shook her head a little ruefully, saying, "Only you can handle wielding two CADs at the same time, Onii-sama."

"If you put your mind to it, you can do it, too." Tatsuya replied with a forced smile, reaching out to rub her head once more. That was his go-to action to improving his sister's mood. The effect was immediate. Miyuki closed her eyes, smiling pleasantly. Seeing that her good mood had returned, Tatsuya returned to business.

"Let's start with a quick examination," he said, his voice cold and emotionless. At this, Miyuki removed her robe shyly and laid down on the calibration machine in her underclothes. Tatsuya began the examination, his movements professional and his face completely expressionless, and he finished it just the same.

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"It's done."

Hearing Tatsuya's words, Miyuki stood up and covered herself once more. Every week, her brother would perform this type of extremely detailed calibration for her. It was something that wasn't available anywhere else, even at the specialist shops. Tatsuya, as usual, had already sat back down at the terminal, continuing his work as if nothing had happened. For some reason, this angered Miyuki to no extent.

"Onii-sama..." she muttered quietly.

Sensing something off in her voice, Tatsuya turned around to face Miyuki. Seeing her glowering expression, Tatsuya said, his voice wavering slightly in uncertainty, "Miyuki?"

It was very rare to hear her brother use that kind of harried voice, and, for some reason, it only made Miyuki's internal temperature rise even further. "I was so embarrassed," she said softly, leaning close to her brother, "And yet you, as always, remained completely expressionless. Did you not feel anything?"

"Umm... Miyuki?" Tatsuya's voice was considerably more panicked, but he didn't know what to say to calm her down.

"And you seem to be very affectionate with Saegusa-senpai, even though you just met! Or is it Watanabe-senpai! Earlier today, your conversation seemed quite close..."

"You heard that!?" Even as Tatsuya asked this, he knew it couldn't possibly be true. She should have been in the Student Council room with Azusa. Furthermore, if someone had been eavesdropping on them, there was no way Tatsuya wouldn't have noticed.

"Ah! Just as expected," Miyuki exclaimed, "Both of them are beautiful, aren't they."

"Hey, Miyuki," Tatsuya tried to interject, "Aren't you misunderstanding something here?"

In her anger, Miyuki seemed not to have heard a word he was saying, however. "This is your punishment!" She cried, drawing her CAD and releasing a surge of Psion waves at him, causing his body to spasm and fall out of the chair.

[Self-Restoration, Auto Start]

[Core Eidos Data, Read from Backup]

[Load Magic Sequence — Complete. Self-Restoration — Complete]

Tatsuya was unconscious for less than a second. In fact, Tatsuya had never been unconscious for longer than that instant. This was his personal magic, his curse.

Tatsuya opened his eyes to see his sister staring down at him.

"Good morning, Onii-sama," she said lightly.

After a moment, Tatsuya replied, "Did I do something to displease you?"

"My apologies," Miyuki said with an angelic smile, "I went overboard with my joke." She reached out hand to help him up.

In the face of her smile, even Tatsuya could do nothing. Besides, wasn't that just like normal siblings playing around? In the end, his little sister was incapable of doing anything that could cause him harm.

Tatsuya sighed and said with a grumble as he grasped Miyuki's hand, "Please, take it easy on me..."

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Miyuki awoke at her normal time, already in a bad mood. In her sleep-muddled state, she panicked a little bit when she couldn't sensed her brother's presence in the house. However, after a moment, she fully awoke and realized he had already gone to his morning training, like he did every day.

In the past, she had been worried the he would ruin his health, going to bed later than her yet still getting up earlier than her. Now, however, she realized such worries were meaningless. Her brother was special. People called her a genius, but they knew nothing. The real genius was her brother. He was so special, he existed in a whole different dimension than them. That true talent that towers over mortals inspires not awe, but terror.

The man that, by all rights, should have been a father to the two siblings had crumpled before that terror, choosing to belittle and abuse his own son rather than acknowledge him. She knew all of this, but her brother believed she remained ignorant, so she pretended that she didn't know.

She pretended she didn't know that, to this day, her father sought to belittle her brother's talent, to give him a sense of defeatism, to pinion the wings of his spirit and ambition.

How comical it was.

Her father had originally sought to imprison her brother, only to be crushed by the talent that far exceeded his own. Her brother had gained the resources he needed to barter for his freedom, and their father was forced to let go, to set him free. The only thing that old man could do was adopt that phony title and collect the hollow praises of the masses.

Miyuki found it difficult to control her thoughts, caught in the state between waking and sleeping. When she had seen her brother acting so harried yesterday, it was so comical and cute. She was happy and safe. But, for some reason, her chest throbbed painfully when they parted ways and she was left alone in her room. She couldn't sleep because of the uneasiness of her heart.

This must be love, she thought. But not romantic love, for he was, in fact, her older brother by blood. She still remembered the moment, three years ago, when she first learned of their relation.

Since that day when he saved me, I have worked hard to be a little sister worthy of him.

I've always had this dream that one day I would be able to help him just as he helped me. I want to become someone he can depend on.

From him, I ask nothing.

This very life should have faded away into the oblivion, but it was saved by him.

Right now, I am only the shackles that bind him, but, one day, I want to be the key that liberates him.

I want to be someone who can help him.

Right now, though, all I can do is let him eat a delicious breakfast when he returns home.

With that, Miyuki smoothly rose, stretching her out as she prepared to face another day.