In hindsight, there had been several clues scattered around me.
Misaki City—the setting of Tsukihime, the work that serves as the cornerstone of TYPE-MOON.
Sister Yuika and the chief priest, who always seemed to use the terms 'Cathedral' and 'Church' interchangeably.
And yet, despite these signs, deducing that this world was the Nasuverse felt like an act of cruel imagination.
’Alice Kuonji... I‘ve only heard the name. She was... a heroine-esque character from the game Mahoutsukai no Yoru.‘
In my past life, my primary exposure had been to the Fate series and Tsukihime. Regrettably, I hadn‘t yet delved into the deep-tier subculture works like Mahoutsukai no Yoru that the hardcore fans enjoyed. Nevertheless, I possessed a cursory knowledge of its contents.
...For example, I knew that the 'Self-Enforcement Geas' she was about to present to me was the very item that had essentially sent Kayneth El-Melloi to the afterlife.
“Now, this is a Self-Enforcement Geas. If you write your name here and sign it... this contract will naturally be engraved upon your soul.”
She thrust a pencil toward me. I looked down at the conditions written on that contract.
’...It‘s a trap.‘
The contract was insidious.
On the surface, it seemed to prohibit 'divulging' information to anyone, but the actual phrasing forbade any action that might reveal her identity.
In other words, interpreted maliciously, simply keeping my mouth shut when questioned about who she was could be construed as 'acting in a suspicious manner that points toward her identity,' which meant I could die on the spot.
The one who drafted the Self-Enforcement Geas was her, the one who judged the violation was her... and I was the only one bearing the risk. It was a nonsensical, absurdly unfair contract.
Judging by the contract alone, it was clear she had no intention of letting me leave alive.
’Well, I suppose this is the average standard for a Magus.‘
But regardless of their standards, my life was precious to me.
My mind raced. Instead of picking up the pencil, I spoke with a trembling voice.
“Are... are you really a witch?”
As an answer, she made several forks and an Easter egg on the side table dance through the air.
After witnessing the display of Magecraft, I began to stare at her intensely again. Eventually, she spoke.
“Hurry and sign. It would be best for you to completely erase today‘s events from your mind, so consider this a mercy.”
I couldn't.
The moment I signed this toxic contract, I would be a dead man.
Both the knowledge from my previous life and the instinct I was born with—tied to the Rinnegan—were screaming that at me.
“...I want to.”
“Hmm?”
Ultimately, I decided to take a gamble in this moment.
“Can I... learn it too?”
I had truly uttered something insane.
* * * * *
The air grew heavy.
As soon as those words left my mouth, I realized it.
Ah, I messed up.
She was staring at me just as she had before, but her gaze was now filled with a coldness that felt as though she were dissecting me alive.
A chill swept over me, making me feel like I might be cut into pieces at any second. My entire body began to shiver uncontrollably.
“Alice! What are you doing there?”
“...Aoko.”
And at that moment, the one who could be called my savior appeared.
The woman with long, straight black hair wearing a warm-looking sweater appeared much younger than the image I remembered, but there was no doubt she was the person I knew. Her name was identical as well.
“You‘ve been asleep for two days, so it looks like you‘ve finally woken up. Did he finish signing the Self-Enforcement Geas?”
“...Hello?”
“Pfft! This kid is interesting... Huh? He hasn't signed the Geas yet. Alice, what's going on?”
“Be quiet, Aoko. This brat is saying something bizarre.”
Aozaki Aoko rounded her mouth into an 'O' in surprise.
“What did he say to make you act like that?”
“He says he wants to learn Magecraft.”
Upon hearing Alice Kuonji's words, Aoko began to burst into laughter, reacting as if someone had just told her an ant had defeated an elephant in a wrestling match.
“Hahaha! So you found this fascinating, did you? Sorry, but... this isn't something we can just teach to anyone. You probably heard the gist of it from Alice, but didn't you almost die once already?”
Aoko, who was famous in Tsukihime for her supposed 'shotacon' tendencies, reached out and stroked my head as if she couldn't suppress that nature.
“Even if the Geas puts your life on the line, it won't actually take your life as long as you don't talk. Forget what happened today and just go home.”
“B-but...”
“Hmm?”
“If I use that... I'll die...”
“I told you, you won't die! The Magecraft inside this contract will absolutely not harm you as long as you don't violate the agreement!”
I had to use my head.
I heard that Aozaki Aoko had a fallout with Alice Kuonji to save me and Soujuurou. That meant she was, at the very least, on the side of preserving our lives.
...I decided to place my bet once more.
“But... I‘m not the one who decides that.”
“...?”
“Look, it says here: ’In the event of an action intended to reveal events related to Magecraft.‘ I can keep my mouth shut, but how can anyone judge whether an action is intended that way or not?”
“It really does say that...? Wait a second, Alice, what is the meaning of this?!”
“...”
The privilege of a child is that you can point out the core of a problem without having to take responsibility for it.
I began to enjoy that privilege while watching Miss Aoko interrogate Alice.
“We had a promise! You said you wouldn't touch those two until we found a way to erase Soujuurou's memories!”
“...If we find the book of Runes, we can erase memories. But this brat isn't at an age where his memories can be safely erased yet, is he? It's better to just kill him.”
“Then what happens to the match at the amusement park? We agreed that I won. Are you planning to break your promise, Alice?”
Before I knew it, the atmosphere between them had turned grim, and something invisible began to undulate in the air around them.
However, Alice was the first to yield, raising both hands, and Miss Aoko calmed the invisible energy as well.
“I still disagree, Aoko. We should lock this brat up for a few months, or at the very least, break his mind.”
“...How is that any different from killing him?!”
“You‘re still like this. Efficiency is the most important thing in Magecraft.”
“Ugh... But the results are already in. The survival I stipulated for those two includes 'leaving their minds intact'!”
The two of them began to bicker with words.
Alice Kuonji was ahead in terms of Magus logic, but since Aozaki Aoko had won their bet, she was using that victory to insist that no brainwashing or mental manipulation be used on me.
“Um...”
“Ah... sorry, we got carried away talking to each other.”
“...If the content of this Geas is the problem, I can change it as much as you want. You can even write what you want, as long as it includes the promise not to divulge anything.”
Alice seemed to want to end this debate and kick me out as quickly as possible, while Miss Aoko seemed to want to protect me from her.
“No, it's not that... Honestly, even if I said you two were Magi, who would believe me?”
“...Eh?”
“Who would seriously believe the words of a third-grade elementary student...?”
“Ah...”
Only then did the two of them look at each other and nod.
“Common sense-wise... if an elementary student says a witch lives in a mansion, would anyone believe that?”
“...Probably not.”
“And if you're worried about me going somewhere and talking before Brother Soujuurou's memories are dealt with, why don't I just stay here?”
“Oh, that's true!”
“What?”
* * * * *
In the end, due to Miss Aoko's strong persuasion and Brother Shizuki's request, I was allowed to stay at the Kuonji Mansion for the time being.
Alice Kuonji accompanied me to explain things to my mother and father. To my surprise, my parents were so moved that I had finally made a friend (an older one at that) that they even shed tears of joy.
“You kept your promise.”
“...You said you'd kill me if I talked.”
“Good. It's best to stay sharp like that. I'll explain briefly, so listen well... Aoko and I are going to find a Rune in this mansion to erase memories. Normally, Mystery must never be exposed to the outside world... but you and Shizuki are exceptions because of Aoko's demand. Do not touch anything in the mansion, and make sure you do every errand the two of us give you.”
With those words, she handed me something resembling a bracelet.
“Wear that at all times... If you try to divulge the Mystery, it will automatically tighten around your wrist.”
“...I understand.”
And so, the cohabitation of four people began: the Witch of Fairy Tales, the future Fifth Magician, an ordinary high schooler, and me.
The biggest thing I realized about the two women after we started living together... was their utter lack of life skills.
“The both of you have zero survival skills.”
I knew from Kara no Kyoukai that Touko Aozaki‘s life skills were so poor she couldn't even pay Shiki Ryougi a proper salary, but I never imagined the sisters would be identical in that regard. To top it off, I hadn't expected Miss Kuonji, who lived with Aoko, to be just as hopeless.
“You two, what is the monthly living budget?”
“70,000 yen.”
“...That is definitely not enough money.”
For four people... although Brother Soujuurou worked a part-time job to earn money and I had an allowance from my parents, it was nowhere near enough for four mouths.
Furthermore, these two were incredibly extravagant spenders. No matter how you looked at it, they were the type to spend lavishly at the start of the month and suffer at the end.
“It can't be helped. For now, Brother Soujuurou, just buy groceries with the money from your part-time job... I think it's better if I do the cooking.”
“Huh? You know how to cook too?”
“...A little.”
It wasn't surprising, but Aozaki Aoko and Alice Kuonji's culinary skills were close to zero.
Even Brother Soujuurou's cooking was limited to grilling things over a fire, so you can imagine the state of things.