I'll find the real killer, and in return, you'll do something for me.
What do you say?"
Yul grew uneasy upon hearing that.
There was something strange about a girl smiling at a time like this.
Then it hit him—she had said something important.
"Officer?
How did you know I worked for the King's Army?
And why would I accept such a deal?
I don't see any reason to help you."
"Well, it may not be obvious, but I'm a pretty sharp detective.
It wasn't hard to figure you out—your posture, your speech, your presence.
Also, someone just died, and you're not the type to just walk away.
In fact, you're more interested in finding the killer than I am.
That's why you want to help me so badly."
For some reason, Yul felt a prick of irritation in his chest.
Maybe because she was half right.
"To be honest, I feel like I'm wasting my time talking to you.
But I don't really mind.
Today's my day off.
If you find the killer, I'll grant any request you want."
He informed the Library Guards that the girl would help them find the culprit, and they allowed her to proceed.
She immediately became absorbed in thought, tuning out everything around her.
She approached the corpse.
The murder had taken place in the middle of the city—right in front of a small bakery, in the pedestrian lane.
There was nothing suspicious around the body.
Looking ahead, she noticed a large open plaza with a giant fountain in the center.
Then, she saw something that caught her attention—a potential clue.
She began to speak:
"After examining the body, I had one major question:
What kind of weapon was used in this crime?
The cut is extremely precise—clean, as if made by a single sword strike.
It's hard to imagine anything else could've done it.
But given the short timeframe in which the crime occurred, using a sword seems impossible."
Yul chimed in, trying to assist her reasoning.
"Regardless of a weapon's presence… is it possible someone moved fast enough to be invisible?
It would make sense if the killer had some kind of special ability.
But if we assume they did, then tracking them down becomes nearly impossible."
The girl stepped between the guards and walked toward the fountain.
"You're right.
But that's exactly what the killer wants us to believe.
With no physical evidence, it's easier to say someone with supernatural powers did it.
But the truth isn't so complex.
The killer just used something… hard to see."
The guard asked with a condescending tone:
"And what might that be?"
"A thread."
She pointed toward the bakery where the murder took place.
"You can check that wooden beam above the storefront.
From a distance, it looks perfectly normal.
But look closer, and you'll see—it's cut clean through in the middle."
That beam supported the bakery's front awning.
It was about seven centimeters thick and had been sliced by something razor-thin.
The gap between each half was no more than ten millimeters.
She then pointed to the fountain next to her and asked the guards to inspect it closely.
As they moved in, they didn't notice anything strange at first—
Until one of them spotted something tied to the central column.
Upon closer inspection, it turned out to be a nearly invisible steel wire.
"What does this mean? Do you know what's going on?"
asked the same guard, who only moments ago looked at her like a criminal, now clearly confused.
"Don't jump ahead, officer.
But yes, as you suspect—this thin wire here is the murder weapon.
It starts at the fountain, wraps around that shop beam, and the end… was likely tied to something at the far end of the street—at least, before the murder took place."
She asked one of the guards what objects were located at the end of the street.
Among the things he listed was a dry well.
When she heard that, she brushed aside the strand of hair covering her eye and said with a tired tone,
"I see.
That's how he did it.
To decapitate someone with a wire like this, you'd need enough tension to slice through flesh and bone cleanly.
That kind of force can't be achieved by human strength.
So, he did this:
He tied the end of the wire to something extremely heavy and compact—then dropped it into the well.
With that force, it could cut through a human body effortlessly."
Yul felt a strange sensation.
Something about the story felt off.
"Wait a minute… if what you're saying is true, then shouldn't you have been hit by the wire too?
You were close enough to have at least been splashed by the victim's blood."
"You're right—if we were the same height.
Fortunately for me, my stunted growth may have saved my life."
"Now that you mention it… that does make sense," Yul said with a sigh, frustrated he hadn't thought of it himself.
The girl continued while examining the steel thread:
"This is fascinating.
The killer clearly has a talent for planning.
But it seems he miscalculated something important."
One of the guards asked, "What do you mean?"
"Look—the wire's been cut in the middle.
It might seem normal, as if it snapped from the weight.
But check the part wrapped around the fountain column.
It almost sliced through the stone.
The killer probably assumed it would cut cleanly through—but what he didn't know was that the column's interior is reinforced with steel rods.
To prevent anyone from discovering the wire, he tried to retrieve it himself—
But when he saw the guards gathering near the fountain, he couldn't get close.
So, he cut the wire and took only part of it with him.
Fortunately for us… he hasn't gone far."
"Wait—are you saying the killer is still here?!"
The girl gave a sly smile and returned to the crime scene.
"To carry out a murder like this, you'd need to observe the area constantly.
And the only place with a perfect view… is that junk shop at the end of the street.
If you hurry, you might still find the wire—or what's left of it."
The guards rushed toward the junk shop with incredible speed, searching it carefully and methodically. After a few minutes, they found the severed wire in an isolated room inside the suspect's space. Meanwhile, Wendy and Yul observed everything from a distance. When Yul realized that everything the girl had said was true, he felt a strange sense of satisfaction deep inside.
"You're truly amazing, miss…
Come to think of it, I haven't introduced myself yet.
I'm Yul, a former commander in the King's army. And you… may I know your name?"
Wendy smiled faintly and replied,
"I'm Wendy. Pleased to meet you.
Now that this case is over, I'd like you to help me a little, Yul. Come with me."