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Kenji
Appraiser, this is a disaster.
A watch approved with a starting price of 13.8 million yen now has a card for 11.8 million yen.
A watch approved with a starting price of 13.8 million yen now has a card for 11.8 million yen.
Appraiser
A difference of 2 million yen can't be explained by a printing smudge.
Kenji
If it were me, the moment I saw that price tag, I'd pull out my loyalty card too.
Appraiser
Before that, the store staff would stop you in your tracks.
CASE FILE 34 Unauthorized Price Reduction on March 1st
- Discovery: March 1st, ordinary year, 7:20 AM, before the charity auction opened
- Approved starting price was 13.8 million yen. However, a starting price card for 11.8 million yen was placed in the exhibition room.
- Exhibition room sealed on February 28th at 7:06 PM. No electronic entry records thereafter.
- Annual calendar watch continuously running on a winder, correctly showing "February 28th, Saturday" when sealed.
- When discovered, it was correctly showing "March 1st, Sunday."
- This model requires manual correction at the end of February in an ordinary year.
- Three individuals had access to the keys, seals, and starting price cards.
① Three Suspects. Those with Keys, Seals, and Pricing Authority
Suspect A: Kohei Todo
47 years old, Auction Security Manager
Can handle emergency mechanical keys. Was in the monitoring room from 4:20 AM to 5:10 AM, with video records and two security guards as witnesses.
Suspect B: Saya Narumi
31 years old, Exhibition Stylist
Manages spare seal stickers. Was working on搬入作业 in an external warehouse from 3:45 AM to 5:20 AM.
Suspect C: Takuma Kiryu
36 years old, Sales Planning and Event Operations Manager
Has authority to issue starting price cards and carries a portable printer. Claims he "was at home until reporting to work at 6:10 AM."
Kenji
Someone with the key, someone with the seal, and someone who can create prices.
If those three cooperated, they could pretty much do anything.
If those three cooperated, they could pretty much do anything.
Appraiser
There's no evidence of cooperation.
First, we need to find out if there's one person who could have done all of it alone.
First, we need to find out if there's one person who could have done all of it alone.
② Kiryu's Testimony — "An annual calendar would automatically change to March 1st, wouldn't it?"
Kiryu's Testimony:
"I didn't enter the exhibition room after it was sealed on February 28th. The watch was running on a winder, so it must have automatically changed to March 1st. It's an annual calendar, after all. The starting price card was either a simple printing error or an old draft got mixed in."
"I didn't enter the exhibition room after it was sealed on February 28th. The watch was running on a winder, so it must have automatically changed to March 1st. It's an annual calendar, after all. The starting price card was either a simple printing error or an old draft got mixed in."
Kenji
Since it's an "annual" calendar, it seems like you could leave it alone for a whole year.
Appraiser
Both Kiryu and Kenji are confusing annual calendars with perpetual calendars.
③ An Annual Calendar: A Calendar that "Needs a Person Once a Year"
Appraiser
An annual calendar mechanically distinguishes between months with 30 days and months with 31 days.
Therefore, it usually doesn't require date correction at the end of each month. However, February, which ends on the 28th or 29th, is an exception. Generally, a manual correction is needed once a year on March 1st.
Therefore, it usually doesn't require date correction at the end of each month. However, February, which ends on the 28th or 29th, is an exception. Generally, a manual correction is needed once a year on March 1st.
Kenji
It's great for 11 months, but then it suddenly calls for help in February.
Appraiser
Exactly.
An annual calendar is a "watch that only needs to be corrected once a year," not a "watch that never needs to be corrected."
An annual calendar is a "watch that only needs to be corrected once a year," not a "watch that never needs to be corrected."
Annual calendar: automatic distinction for 30 and 31 days / usually one correction at the end of February
Perpetual calendars, if correctly set and continuously running, mechanically process 28 and 29 days, as well as leap years.
Differences in Common Calendar Mechanisms
| Type | Detection of days in month | Typical correction frequency |
|---|---|---|
| Standard date display | Does not automatically detect 30 days, 31 days, or February | Generally 5 times a year, on the day after months with fewer than 31 days |
| Annual Calendar | Detects 30 and 31 days. Does not typically detect the shortness of February. | Generally once a year, from end of February to March 1st |
| Perpetual Calendar | Detects 28, 29 days, and leap years. | No annual correction required, assuming continuous operation and correct setting. |
④ February 28th, 7:06 PM — The display and price were correct at the time of sealing.
Confirmation Record Immediately Before Sealing
| Date/Time | February 28, 2026 (Sat), 7:06 PM |
|---|---|
| Calendar Display | February, Saturday, 28th, matched actual date |
| Operating Status | Watch was running, display winder also operating normally |
| Starting Price Card | Officially approved 13.8 million yen |
| Seal | Seal number S-3148. Confirmed by 3 people: Appraiser, Kiryu, and record keeper. |
Kenji
Both the date and the price were correct when it was sealed.
Then both conveniently changed sometime in between.
Then both conveniently changed sometime in between.
Appraiser
And the winder only keeps the watch running.
It doesn't make the correction for the end of February for you.
It doesn't make the correction for the end of February for you.
⑤ On the morning of March 1st, only the watch knew the correct date.
Exhibition Room Before Opening
| Date/Time | March 1, 2026 (Sun), 7:20 AM |
|---|---|
| Calendar Display | March, Sunday, 1st, matched actual date |
| Starting Price Card | 11.8 million yen, 2 million yen lower than the approved amount |
| Winder | No stop record. Watch also operating normally. |
| Electronic Entry History | No records after sealing. |
Clue for Readers:
This annual calendar, by simply continuing to run, cannot correctly transition past the end of February in an ordinary year. If it changed from "February 28th" at the time of sealing to the correct "March 1st" when discovered, it is natural to assume that someone intervened with the calendar during that time.
This annual calendar, by simply continuing to run, cannot correctly transition past the end of February in an ordinary year. If it changed from "February 28th" at the time of sealing to the correct "March 1st" when discovered, it is natural to assume that someone intervened with the calendar during that time.
Kenji
So, the person who fixed the date is also the culprit who swapped the starting price card.
⑥ However, a correct date alone doesn't make a "culprit."
Appraiser
Not yet.
What the display tells us is only that someone intervened with the watch after it was sealed. It's not necessarily the case that the person who corrected the date with good intentions is the same person who swapped the starting price card.
What the display tells us is only that someone intervened with the watch after it was sealed. It's not necessarily the case that the person who corrected the date with good intentions is the same person who swapped the starting price card.
Kenji
So, the watch doesn't reveal the culprit's name, but only that "the March 1st display was manually set." Is that right?
Appraiser
That's right.
The person who operated it, the time, and the motive must be established with other evidence.
The person who operated it, the time, and the motive must be established with other evidence.
What an Annual Calendar Can and Cannot Tell Us
| What it can tell us | What it cannot tell us alone |
|---|---|
| Under these conditions, it is highly probable that correction occurred between the night of Feb 28th and the morning of Mar 1st. | The name of the person who made the correction. |
| The explanation "it's an annual calendar, so it automatically changed to the correct March 1st" contradicts this model's specifications. | The exact time of the operation. |
| We should question the assumption that no intervention occurred after sealing. | Whether date correction and starting price card exchange were done by the same person. |
⑦ A seal of the same color. However, the number and opening/closing records were different.
Re-examination of Seal and Service Door
| Seal Number at Time of Sealing | S-3148 |
|---|---|
| Seal Number at Time of Discovery | S-3194. Same color and shape, but a different sticker. |
| Spare Roll | The roll containing S-3194 was lent to Kiryu, the event operations manager, on the night of February 28th. |
| Alarm Status | Temporarily disarmed from 4:38 AM to 4:55 AM using Kiryu's personal maintenance code. |
| Service Door | Opening/closing sensor activated at 4:41 AM. No regular badge history due to emergency key use. |
| Key Storage Box | Opened at 4:39 AM with the same personal maintenance code. |
Kenji
So the seal wasn't still there; it was replaced with a similar-looking one.
Appraiser
Operating by color alone is dangerous.
A seal only becomes a seal when its number is also verified.
A seal only becomes a seal when its number is also verified.
⑧ The starting price card, 2 million yen cheaper, came from Kiryu's portable printer.
Verification of Starting Price Card and Portable Printer
- Management data for the swapped card shows an issuance record of March 1st at 4:43 AM.
- The operating user was Kiryu's work ID.
- The output destination was portable thermal printer P-03, assigned to Kiryu.
- At the time of printing, P-03 was connected at close range to Kiryu's work smartphone. That device was connected to the in-house Wi-Fi near the service door at the same time.
- A part of P-03's thermal head is missing, causing a thin white line in the same position on printed materials.
- The 11.8 million yen card also has a white line of the same width and in the same position.
- Kiryu changed his explanation to "my ID might have been used illegally."
Kenji
So even the printer signed its own name with a white line.
Appraiser
A machine's quirks can sometimes become its signature.
⑨ Crime Reconstruction - Changed the price, then adjusted the date.
Kiryu's Actual Actions
- Made a verbal promise to a key client that the watch could be provided for 11.8 million yen, before official approval.
- Formal price reduction request was denied, but fearing the loss of the client, decided to alter the price.
- At 4:38 AM, disarmed the alarm with his personal maintenance code and retrieved the emergency key.
- At 4:41 AM, entered the exhibition room through the service door.
- Printed an 11.8 million yen card with his portable printer and swapped it for the official card.
- Since a February display at opening time would be unnatural, he corrected the calendar to March 1st according to this model's operating procedure.
- Applied a spare seal S-3194 to make it appear unopened.
- At 6:10 AM, entered through the main entrance, feigning a normal arrival for work.
Appraiser
Kiryu didn't just change the price tag.
To make the tampered display look natural, he even adjusted the watch's date.
To make the tampered display look natural, he even adjusted the watch's date.
Kenji
He lowered the price, but only raised the completeness of the evidence.
⑩ The culprit is Takuma Kiryu, Sales Planning and Event Operations Manager.
The one who knew it was March 1st wasn't the watch, it was "you."
Appraiser: "Mr. Kiryu. You did not arrive for the first time at 6:10 AM. You entered the exhibition room in the 4 AM hour and swapped the starting price card and the seal."
Appraiser
The correct March 1st display on the annual calendar merely indicated intervention after sealing. That alone wasn't enough to identify you as the culprit.
However, the swapped seal number, the door sensor at 4:41 AM, your maintenance code, the printing record at 4:43 AM, and the unique white line from P-03 linked you to both the intrusion and the starting price card exchange. Furthermore, your work device, connected to P-03, was connected to the in-house Wi-Fi near the service door at the same time. Your explanation that your ID was stolen also does not hold up.
You finally corrected the date to make it seem as if "this was the state from the beginning."
However, the swapped seal number, the door sensor at 4:41 AM, your maintenance code, the printing record at 4:43 AM, and the unique white line from P-03 linked you to both the intrusion and the starting price card exchange. Furthermore, your work device, connected to P-03, was connected to the in-house Wi-Fi near the service door at the same time. Your explanation that your ID was stolen also does not hold up.
You finally corrected the date to make it seem as if "this was the state from the beginning."
Kiryu's Confession:
"I had promised a long-time client that I could secure it for 11.8 million yen. When the price reduction request wasn't approved, I feared losing the client. I thought if that price was displayed from the opening, the company wouldn't be able to ignore it on the spot. I adjusted the watch's date because it would have been unnatural for it to still show February in March."
"I had promised a long-time client that I could secure it for 11.8 million yen. When the price reduction request wasn't approved, I feared losing the client. I thought if that price was displayed from the opening, the company wouldn't be able to ignore it on the spot. I adjusted the watch's date because it would have been unnatural for it to still show February in March."
Kenji
To keep a promise with one person, he broke a much bigger promise.
Appraiser
Neither price nor trust can be arbitrarily adjusted.
⑪ After the Incident, Kenji Insists Last Year's Desk Calendar is a "Perpetual Calendar"
Kenji
Appraiser, I also had a perpetual calendar.
It's last year's desk calendar. The March page is still usable.
It's last year's desk calendar. The March page is still usable.
Appraiser
All the days of the week are off.
Kenji
I'll correct that once a year with a permanent marker.
It's a sustainable complication.
It's a sustainable complication.
Appraiser
(Don't use new words to extend the life of an old calendar...)
Conclusion: The Annual Calendar Revealed Intervention That Cannot Be Dismissed as "Automatically Changed."
Appraiser
The annual calendar is a practical complication that distinguishes between 30-day and 31-day months, significantly reducing the need for monthly corrections.
However, generally, only the end of February requires manual adjustment to the actual date. It is not a mechanism that automatically calculates leap years like a perpetual calendar.
This time, the annual calendar, which was correct when sealed on February 28th, was still displaying correctly on the morning of March 1st. Since the watch had been running continuously, the explanation that "it automatically became the correct March 1st because it's an annual calendar" contradicts the specifications of this model.
However, the culprit was not identified solely by the display. Kiryu's actions were proven by combining the seal numbers, service door records, maintenance codes, records of issued starting price cards, unique printer marks, and connection records of the business terminals.
The annual calendar does not point to the culprit. But once a year, it demands correction from human explanation.
However, generally, only the end of February requires manual adjustment to the actual date. It is not a mechanism that automatically calculates leap years like a perpetual calendar.
This time, the annual calendar, which was correct when sealed on February 28th, was still displaying correctly on the morning of March 1st. Since the watch had been running continuously, the explanation that "it automatically became the correct March 1st because it's an annual calendar" contradicts the specifications of this model.
However, the culprit was not identified solely by the display. Kiryu's actions were proven by combining the seal numbers, service door records, maintenance codes, records of issued starting price cards, unique printer marks, and connection records of the business terminals.
The annual calendar does not point to the culprit. But once a year, it demands correction from human explanation.
Annual Calendar Lessons from the Case
- Mechanically distinguishes between 30 and 31 days: A practical complication that reduces normal end-of-month adjustments.
- Generally requires annual correction only at the end of February: Does not process the short month of February in common and leap years like a perpetual calendar.
- Winder does not correct: Even if the watch is kept running, the annual correction is not automated.
- Cannot identify a person from the display alone: Use in combination with other evidence as a clue to suspect manipulation.
- Correction methods vary by model: Operating systems such as crown, bezel, and dedicated corrector are not uniform.
- Evaluation is not determined by mechanism name alone: Comprehensive consideration of brand, model number, movement, exterior, service history, accessories, and marketability.
*This work is a fiction set with an "annual calendar that requires manual correction at the end of February in a common year, and was continuously running on a winder before being sealed." The day requiring correction, operating method, number of operations, display progression, and times to avoid operation vary depending on the model and caliber. Forcing correction while the switching mechanism is operating may lead to damage, so always follow the instruction manual or the guidance of an authorized service center or specialist shop for actual watches. It is not possible to identify the person operating, the time, or the purpose solely from the display.
Key deduction points this time
- When sealed on February 28th, the watch was running continuously with the correct display.
- This annual calendar cannot correctly pass the end of February in a common year by natural operation alone.
- Intervention after sealing was suspected due to the correct March 1st display.
- Connected the person and the alteration of the starting price with seal numbers, door sensors, maintenance codes, print records, and terminal connections.
- Understand the difference between annual and perpetual calendars, and do not determine value or condition solely by the mechanism name.
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