The Necklace That Should Not Exist
…Huh?
In the dark room, lying in bed, she turned over what had happened a little while ago — the way she had clutched Emily's small body tight and burst into sobs like a child.
"Nnngh…."
Thump!
Thump!
The blanket jolted.
Embarrassing. So embarrassing she could die.
She didn't regret giving herself over, for that one moment, to the feeling that had spilled out of her. Even so, shame was still shame.
"Haaa…."
Her roommate still hadn't come back. Tomorrow was the entrance ceremony, which meant tonight was the last time she would be able to be alone like this.
"Aaaah!!!"
Thump! Thump-thump!!
She kicked the blanket hard again. Once today was over, she wouldn't be free to do this sort of thing whenever she pleased, so she had to do it while she still could. The blanket shuddered once more, and Mariella found her composure again.
And once the feeling had settled, something else rose in its place.
A question. To be precise…
Clink.
She shifted her hand, and metal chimed from beside the pillow. The choker Emily had given her was there. Mariella took hold of it and brought it up before her eyes.
It was a dark night, but looking at a choker held right in front of her face was no trouble. Part of it was that she saw well in the dark; part of it was that she hadn't drawn the curtains, so the light from outside softly lit whatever lay before her.
…As expected. It looked like an ordinary choker.
To the eye and to the hand, it was nothing but an ordinary choker — though a little too heavy, and too crude, to really deserve the word.
…No. It was just a dog collar. However she tried to dress it up, the words dog collar insisted on coming to mind.
Stop anyone on the street and ask, and a hundred out of a hundred would call it a dog collar. Even so, Mariella knew. This necklace was not merely a dog collar.
"…I'm certain of it. What happened then was real."
Her eyes were open, and still it drew itself vividly in front of them: crystals blooming into beautiful flowers, and that current running the length of her body, hot and cold at once, impossible to put into words.
She looked at the necklace again. Calling up the memory of that moment, she let a thin thread of mana flow into it.
And then—
A faint hum. A pale blue light traced the necklace, circled once, and vanished.
"How did she even make something like this…?"
After the question came admiration.
In modern magical theory, three things had to come before a spell could be cast.
The first was mana. Obvious enough. Magic was the use of mana. Where in the world was there a fire that burned without fuel?
The second was the circle. If mana was a tree grown straight and tall, the circle was the woodcutter. Just as a woodcutter split green timber into fuel, a circle took in mana from outside, circulated it, and converted it into a form fit for casting. That was why the presence or absence of a circle decided whether a person could use magic at all.
The third, and last, was the wand. A wand served as the spark. Mana or no mana, circle or no circle, without a wand you could not cast.
Those were the three conditions for using magic.
…Well. Thanks to a certain someone's paper, that last one currently sat at the very center of a furious controversy. The accepted doctrine hadn't been entirely overturned yet, though.
"…But does anyone else even know about this?"
After the admiration, a thin thread of fear welled up.
Of the three elements she had just named, the second — the circle — was thoroughly innate. It might manifest late, but a circle did not simply appear in someone born without one. There had been no shortage of attempts to create circles artificially, and a few had even succeeded… only for the result to be failure all the same. Circles made that way never lasted two years before they vanished.
But this thing in front of her — wasn't it, looked at a certain way, an artificial circle?
The thought sent a chill up the back of her neck.
What was this necklace, really? A tool that tuned a distorted circle until magic became possible? Or was it truly an artificially made circle, one you could put on and take off from the outside? The former would be an extraordinary object. The latter would be a frightening one.
Because if it was the latter, then mass-producing this necklace alone would mean mages could be made without end.
An object that dragged the worth of a mage down through the floor. That was what this necklace was.
If other mages ever realized it, they would use any means necessary to wipe both the necklace and its design from the world.
The moment she thought that, strength gathered in her hand of its own accord.
"……."
She didn't actually know whether handing this necklace to someone with no circle would let them cast the same way. She hadn't taken it apart and analyzed it, so there was no way to tell. But there was no harm in being careful, was there?
This… I hide it. As thoroughly as I can.
And at the same time—
"……No. Is it really all right to just hand something like this over?"
Anger surged.
Does that girl go through life without a single thought in her head? Why do I have to be the one worrying for her? Don't give away something this dangerous as if it were nothing…….
No. I am grateful. But….
"Haaa……."
A sigh escaped her.
For now, this necklace… she was going to have to talk it over with her sister as soon as she could.
"I should just sleep…."
Tomorrow was the entrance ceremony. She had been chosen as one of the representatives of the incoming students, so she would have to rise earlier than everyone else and get ready. She closed her eyes and, slowly, gave herself over to the drowsiness closing in——
"Mmm…."
"What are you staring at so hard, Master-nyang?"
"The auxiliary circle I handed Mariella earlier isn't matching my prediction. I'm looking into the cause."
"…Didn't you say the entrance ceremony is tomorrow-nyang?"
"Don't worry. I'm not planning to clutch this all night…."
"Mmm…… Well, Master will handle it just fine, right…? Then I'm sleeping first-nyang…."
With a soft leap, Nero sprang up onto the bed. He curled himself into a round ball in the middle of the blanket, and before many minutes had passed a rumbling little purr could be heard.
Fast asleep already. This was going to take me a while longer….
The schematics turned with a dry flutter, one sheet after another. Page by page, I went over every last character.
"That's strange……."
The choker — I had roughly named it something along the lines of an Externally Detachable Auxiliary Circle. Though calling that a formal designation felt a little off. It was only the name I'd stuck on it myself.
It had been a thing I could never present to anyone, left to rot in a corner of storage, so there had been no need to give it a proper name. Calling it whatever was convenient for me had been enough. But now that I'd given it to someone — to Mariella — just calling it a choker felt wrong.
In any case, an externally detachable auxiliary circle was exactly what it sounded like: an auxiliary circle worn and removed outside the body.
…Right. An auxiliary circle. Its role was only ever to assist the circle that belonged inside the body. It wasn't incapable of functioning on its own, but the efficiency collapsed. If, while assisting, it converted an input of 100 at something like eighty to ninety percent, then running alone it took an input of 10,000 just to scrape together a 1.
I hadn't run all that many clinical trials, so the statistics weren't perfect… but the margin of error had been around 0.1 percent at the outside, which meant it was fair to say there was no error in the theory.
So if my calculations were right, the choker should never have been able to cast magic on that scale. There simply hadn't been enough mana for it. With that amount, the best you could manage was second-circle magic — and only the very lowest grade of it, barely.
"…So what went wrong……."
Mariella's circle was impaired. Using it put a severe strain on her heart — serious enough that one mistake could kill her. That was why I had deliberately worked the mana alongside her, casting so that the circle in her heart was never touched at all….
By the math, that ought to have produced the same efficiency as running the auxiliary circle by itself. So why had it turned out like this?
I could go straight to Mariella, take the choker back, and check it in person. But it was late, and snatching back something I'd given as a gift felt a little wrong, so here I was, checking it against the schematics instead… and I still couldn't tell what the problem was.
"Mmm……."
What was the problem?
"Hah…."
Sleep was creeping up on me. I glanced at the clock and found it was already past midnight.
"I should stop here."
I still had to prepare for tomorrow's entrance ceremony. I couldn't keep clinging to this.
Something going wrong at an entrance ceremony was common sense, wasn't it? A raid by some hostile organization. A test aimed at the students. They had gone so far as to send me on escort duty, which meant they must have noticed that something was off.
That was why I had at least given Mariella a brooch enchanted with protection magic — but that alone left me uneasy….
Unauthorized magic couldn't be used inside the Academy, so whatever I brought had to be something that wouldn't stand out.
…But what was I supposed to bring?
"……."
The worrying dragged on.
I needed to get ready quickly and sleep.
"………Huh?"
This was bad. I should have suspected something the moment waking up felt strangely refreshing.
Pushing the uneasy feeling aside, I slowly checked the clock.
The entrance ceremony began at nine.
"W-wait—?!"
"Ah…."
I was screwed. I'd overslept.
I was late, wasn't I?