Becoming Professor Moriarty’s Probability

“… I’m not Adler.”

As Mycrony Holmes slightly opened her lidded eyes and entered the room with a bright smile, Adler, still seated, averted his gaze and muttered.

“I’m sure I told you… If you just keep your promise, I’ll turn a blind eye this time no matter what you do.”

“Was Mr Adler always the kind of man who couldn’t even keep such a simple promise?”

While glaring directly at him, Mycrony Holmes continued speaking with a trace of mirth in her voice.

“… Aren’t you going to answer?”

While a bright smile lingered on her lips, her faintly opened eyes did not share the same mirth, arctic chill permeating in them instead.

“What’s going on here, sis?”

“Can’t you see I’m dealing with a case request right now?”

Unable to bear it any longer, Charlotte Holmes interrupted their conversation.

“If you have something to say, say it later. I’m busy right n…”

“Charlotte, have I ever come to this boarding house on my own accord?”

Yet Mycrony, still staring intently at Adler, spoke with a fixed gaze.

“… Never.”

“Then you should be able to sense that this isn’t just any ordinary matter, right?”

With that, a brief silence ensued in the room.

In that brief silence, the sharp gazes of the two sisters collided in mid-air.

“Are you trying to meddle in my case now?”

“Well… I haven’t done anything yet.”

“The fact that you, who usually shut yourself away like a hermit, have dragged your bloated frame all the way here seems like a silent threat to me though.”

“… Our Charlotte still has a very foul tongue it seems.”

As Charlotte opened her mouth first in the tense situation, Mycrony sat down on the sofa next to her, a distinct gloom in her eyes.

“If I end up getting so weak that I die, I wonder if she’ll even shed a tear then…”

“… Enough, tell me why you’re here.”

“Always so prickly…”

As Charlotte fiddled with an unfinished cigarette, sniffing it, Mycrony began muttering in a low voice.

“Charlotte. Do you remember what I always used to say since you were a little girl?”

“That nonsense again?”

“The detective’s weakness is authority. The authority that ordinary civilians are absolutely helpless against.”

“I’m not a detective, I’m a consulting investigator. And that fact works the other way around too, doesn’t it?”

At Charlotte’s sharp retort, Mycrony burst out into a peal of unrestrained laughter.

“… Right, that’s true. But that’s only when the detective holds material evidence of the authoritarian’s weakness.”

“Furthermore, that authoritarian has to not be me.”

“What exactly are you planning?”

As Mycrony dropped her playful tone, Charlotte clenched her fist and asked in a sharp tone.

“You’re not usually like this, are you? Sure, you always carry dark secrets around, handling all sorts of dirty work on behalf of the government… but I thought you stood for justice?”

“… Something like that, yes. However, my definition of justice is slightly different from yours, little sister.”

Mycrony responded with a sigh.

"My definition of justice is the peace and tranquillity of the British Empire."

"If that were to be violated, from my point of view, I deem that an act of evil."

Her expression was more serious than ever.

“As a detective operating in London, there’s hardly ever a chance for you to cross that line I have set forth. Even if you occasionally handle international cases, as you do, it usually benefits Britain’s national interests directly.”

“So…”

“But having analysed the potential outcomes of your involvement in this current case from various angles… I felt I had to intervene.”

As her words ended, a chilly atmosphere descended upon the boarding house.

“Are you telling me to back off from this case?”

“Um… I’d like to say that. But you probably won’t accept it straightforwardly, will you?”

As the atmosphere lingered, Charlotte silently stared down at her sister and asked. In response, Mycrony scratched her head, looking troubled.

“You know me well. I understand your position, but I don’t think that’s enough to stop me…”

“That’s why I’ve prepared a little gift for my cute little sister.”

The next moment, a newspaper was thrust in front of Charlotte.

“A gift, what…”

As Charlotte looked down at the newspaper, her expression suddenly hardened.

Advertisement: Looking for a Missing Person

– Age: 19

– Description: Asian female with black hair and eyes. Speaks neither Chinese nor Japanese. Missing for about two weeks. Will be rewarded generously for any information of her whereabouts.

“… It was published in most of London’s newspapers this morning.”

Mycrony watched her in silence for some time, then whispered in a low voice.

“The criminals will be alternating between surveillance and torture in the morning, and they’ll likely see the newspaper over a late lunch. Adler left that place not long ago too.”

“… Shit!”

“By now, all hell must have broken loose, right?”

Charlotte’s complexion turned pale as she quickly got up and threw on her coat.

“Watson! Grab your gun and follow me! We’re in a hurry!”

“… Huh? Oh, uh, okay!”

“Let’s catch a carriage right now!”

Following her cry, Watson, who had been sitting dumbfounded in a corner up until then, picked up her gun with a flustered expression and started following Charlotte with haste in her steps.

“Good luck, little sister~”

“… Hmph.”

Just as Charlotte, accompanied by Watson, was about to step out of the boarding house, a voice came from behind, causing her expression to turn cold as arctic snow.

"I'm disappointed."

And then, with a voice that mirrored her frigid expression, she spoke to her big sister— her own flesh and blood.

"... What makes you any different from the professor, huh?"

With those words, the door to the boarding house closed, and soon silence descended in the lonely room.

“That is… a rather cutting remark, isn’t it…?”

In that silence, Mycrony Holmes smiled bitterly as she rose from her seat.

“… Welp, can’t help it. That’s my job, after all.”

“Then Mr Adler, take care of yourself too. I gather you’re withdrawing from this ca…”

“… Don’t try to fool me, Miss Mycrony.”

As she waved her hand and headed for the exit, Adler’s soft voice made her halt.

“It’s not because of mere loyalty and affection for Britain that you did this, right?”

“Pardon?”

“You did it for your little sister, right?”

“Why do you think so?”

Then, without turning her head, she asked in a low voice. Adler responded just as softly,

"If you die in six months, you won’t be able to watch Charlotte's back anymore now, would you?"

Hearing his response, Mycrony flinched again.

“So, you orchestrated this to protect your precious little sister from the higher-ups while giving her a lesson about the reality of this world, didn’t you?”

“How did you find out that I was terminally ill? I’ve even deceived my own doctor, then how?”

“… How much of your blood do you think I’ve consumed?”

“Oh my lord, how embarrassing!”

Despite her usual relaxed smile and light-hearted banter, she couldn’t hide the slight tremble in her voice.

“Good thing I had cast a spell to prevent eavesdropping, or my cute little sister would have found out that salacious secret…”

“It honestly looks like you’re barely able to stand on your own right now. Shall I support you?”

“Looks like you’ve gotten rather full of yourself.”

Adler looked at her with a sympathetic gaze and whispered to her. In response, Mycrony opened her mouth as well to retort.

"You're terminally ill too, aren't you?"

“I don’t know what you are talking abou…”

"Don't think about denying it, you have exactly six months left just like me."

Initially, Adler scowled and attempted to deny it, but upon Mycrony accurately guessing even the remainder of his left on this world, he surrendered with a tired sigh.

"Yes, so I'm going to take things seriously from now on."

- Click…

At the same time, Adler pressed on his ear, sending a signal somewhere.

“… Holmes has moved. Proceed as planned.”

“Haa.”

“I’ve been too playful, haven’t I? Distracted by women.”

Mycrony looked at her, momentarily caught off guard by his sly remark, then burst out into a peal of unrestrained laughter.

"... As expected, you knew I'd place an advertisement in the newspaper, right?"

“Even using that as part of your plan. Like a convenient chess piece.”

"... I too have to start doing things properly at some point, right? Better start from now.”

Upon receiving Adler’s confirmation, Mycrony’s cheeks blushed pink and she embraced herself tightly, her body writhing.

“Being seen through by someone is a first for me…”

“It feels like I’m stripped bare in front of everyone, completely naked. This is a new thrill…”

Shivering for a moment in that state, she gazed at Adler as he started putting on his coat and asked him,

“… Hey, how grand a scheme are you envisioning?”

"I can't tell you about that, but I can say that it will end at a certain waterfall."

With those meaningful words, Mycrony started gazing at Adler with a slightly different expression than before.

“Well, I will do my best to complete my plan within the next six months.”

“So, let’s not get in each other’s way, okay?”

Leaving her behind, Adler silently paced toward the door.

“You know.”

As he grabbed the doorknob and was about to step outside,

“Am I included in that scheme somehow?”

She queried in a barely audible voice.

“I just had a thought, for the first time in my life, I genuinely don’t wish to die.”

“… That’s unexpected.”

“Hey, how about dating me instead of my sister? Just for six months.”

Adler paused for a moment, before opening the door and stepping out. A faint voice echoed in the air, carrying his reply,

“… Sorry, but I’m already married.”

And in the ensuing silence, Mycrony Holmes muttered to herself,

"Really, he's such a fascinating man. The more I get to know him, the more he makes me fall."

Her unchanging grey eyes brightened ever so slightly as she gazed at his visage.

"... Can’t I just have three months with you before I die?"

.

.

.

.

.

The next morning. In a remote countryside of Britain, some distance away from London,

- Clink…!

... Uh?

A girl, momentarily knocked unconscious by brutal torture, slowly lifted her head at the sound of the cell opening.

- Thud…!

“Ouch…”

Then, a face she had become familiar with was thrown down beside her.

M-Mr Interpreter.

... Yes, it's me.

Adler, grimacing as he fell on his bottom when he landed on the cell, soon answered with a bright smile. Seeing him smile, the girl began with a hopeful look in his eyes.

Wa-Was the plan successful?

C-Can we leave now...?

But.

No.

I've been captured too.

The answer that Adler returned, contrary to her hopes, was like a bolt from the blue, stunning her for a few seconds.

So what do we do now...?

It's alright.

Wh-What's alright, dammit!? They're filled with thoughts of killing me instead of torturing now. It's over...!

Only then did the girl notice the rope tied around Adler’s body and began lamenting in a sobbing tone.

Why give me hope if this was to happen...? There's nothing crueler than being given hope only to have it taken away...

It's alright, I tell you.

What exactly is...!

I let myself get captured on purpose.

Adler began reassuring her with a soft voice.

W-Why on earth?

To find out where you had been taken.

But what about after this...

Don't worry. If something had gone wrong, by now a Buster Call¹ would have been dropped on the world’s strongest powers.

Buster... what?

... Just watch.

Laying down completely, he muttered in a relaxed voice.

Even if that wasn't the case, my subordinate has just...

- Screech…

Right, they've just arrived.

Then, as the cell door opened again, Adler lifted his body with a smirk plastered on his face.

It's time to escape...

But it did not take long for his relaxed expression to harden.

“Hello, yes?”

The person who opened the cell door, instead of Princess Clay disguised as an interpreter,

“I am just an oldinary Asian intelpretel.”²

Was actually Charlotte Holmes, disguised and speaking similarly to how he had the day before as he visited her.

W-Who...?

“… Switch to Plan B.”

Adler frowned for a moment at the situation, then sighed and raised his hand to his ear to send a signal to his subordinates.

- So there’s a Plan B too?

… At this point, it’s wise to include a plan when things don’t go according to plan.

Good eve… ning?

“… Huh?”

But as a slightly awkward Korean slipped out of Charlotte’s mouth, this time, even his well-prepared brain came to a screeching halt.

You understand, right...?

Charlotte murmured in awkward Korean, watching Adler with a sinister smile on her face.

1. One Piece reference.2. She is mimicing how Adler talked to her disguised as an interpreter. It is addressed in the following line.