He looked through it for a while, and then said:

"This should be it."

"Doctor, we've found it!" Ayumi said.

But when the others looked up at Professor Agasa, they found that he was holding the postcard with the cute handwriting.

He looked down at the postcard, a look of reminiscence on his face.

Several people called out to Professor Agasa before he came to his senses.

"Doctor, did you find something interesting?" Genta asked curiously.

"It's that postcard the child wrote earlier!" Ayumi simply stated what it was, without any ulterior motives.

The precocious Mitsuhiko made a casual guess:

"Doctor, could it be that a love letter someone gave you when you were a child?"

Upon hearing this, Dr. Agasa blushed slightly.

Even Mitsuhiko himself didn't expect it.

He guessed casually, and surprisingly, he was almost right.

Although the postcard wasn't a love letter, and the two of them may not have realized the feelings behind it back then, it did indeed have the feel of a love letter.

A ten-year promise is indeed quite romantic.

"No," Professor Agasa explained, blushing. "This is a postcard that a friend gave me a long time ago."

"That happened forty years ago."

"Forty years ago?" Conan was somewhat surprised.

After calculating the time, Guangyou asked:

"You must have been in sixth grade back then, Doctor?"

"Yes." Professor Agasa nodded.

As he reminisced, he recounted that period of time to the group:

"I remember that day was the first day after summer vacation ended."

"Because I was going to be late, I took a shortcut."

"As a result, we saw a young girl hiding behind a telephone pole."

"He looks very scared."

"The dark, wide-brimmed hat couldn't hide those big, bright eyes."

"At the time, I thought, what a lovely girl."

"Because I heard the dog barking, I guessed that she was afraid of the big dog barking in front of her, so she didn't dare to go over."

"That family is the Noi family, who are famous in that area for raising large dogs."

"So there was no other way, so I had her hide behind me, and I faced the door and walked sideways to the other side, and that's how I got through."

"Because there was a gate blocking the way, she was still so scared, so I asked her why."

"She told me it was because she was bitten by her own dog when she was a child, and she has been afraid of animals ever since."

"Especially those that look particularly fierce."

"I have some psychological trauma because of that experience."

"After I learned the reason, I said that it was too pitiful."

"After that, I took her to the home of a friend of mine named Chōno."

"Because Chōno kept a golden hamster."

"At first she was very scared, but over time she got used to it."

"After two months, she rediscovered her love for animals."

"Even if it's the Noi family's doorstep where they keep a large dog, she can still walk past with a smile."

At this point, Dr. Agasa smiled.

Clearly, even after forty years, he was still happy about the girl's transformation.

...