Faced with the looks of three people who seemed lost and didn't understand what she was talking about, the detective had to face the facts. She would have to explain everything, from the beginning.
"When you told me that you had changed the locks, I wondered if it was really justified to come to this." She said. "After all, you thought the person had come in through the window. And the only thing that convinced you to change the lock on the door was your landlord. However, he confided in me that he did not do anything more than that, to ensure the safety of his tenants."
Oh. That's right. Now that I thought about it, we had run into the man in question that evening. He seemed like a helpful person. But, I don't know why, at the time he seemed rather suspicious and wary of the detective and myself. It was as if he was used to being suspicious of strangers. Perhaps that was why he had squinted his eyes, while looking at us.
"I then checked the gate separating the courtyard from the living quarters, and I could see that it was an old lock system," the detective continued to explain. "This kind of system relies on the use of access codes and badges, and is even quite easy to foil and break into, truth be told."
So that was what she was checking, looking closely at the portal in question? At the time, she just seemed to be taking pictures, nothing more. It was quite disturbing to discover things you didn't know about events you had witnessed.
The detective, on the other hand, took a lot of pleasure in revealing everything she had discovered. A bit like in those old detective shows on TV, where the police inspector would explain his reasoning and expose the culprit in front of a crowd.
Yet, even though she told me to stop watching TV, she was acting like an old TV show cliché.
She had exactly the same presence in the room to me as they did in those soap operas - and probably liked to control things - because she then turned to Ms. Munehara, and added:
"You yourself gave us the access code to get in. And that code is your personal code. This means that you are the only one who can normally use it, and that each person in the residence has his own code, in addition to a unique access badge." She explained. "Which logically allows you to know who's coming in or going out."
Then she went and sat down on the bed right next to me, and leaning toward me, she said loud enough for everyone to hear:
"Now, Nijima-kun, do you remember seeing me type in the code in question, when we came back later that evening?"
The movement in question didn't bother me at all, though I suppose most people might have been made uncomfortable by such sudden proximity. For my part, it didn't make me feel hot or cold, even when it was her approaching me like that. So I was already thinking about my answer.
What if I remembered?
Let's see...
We had talked with Mr. Yoshikawa, and then she had presented me her vision of the detective job. How discretion was the best asset an investigator could have.
However, our discussion had started in the courtyard, and had ended without any noticeable interruption on the stairs leading upstairs.
Oh.
I had finally realized this, and to give voice to my discovery, I replied:
"I don't even remember going through the gate," I said.
She smiled, confidently, and straightened up completely, with the corner of her lips slightly raised, as if she were pleased to see me answer so vaguely.
"You don't remember, because I didn't linger to type in the code. I used another method for that," she said mischievously. "It is indeed possible to unlock the lock very simply: by lifting the gate slightly on its hinges, while passing a magnet against the badge reader."
Ms. Munehara was very surprised to hear this, as she immediately brought one of her hands to her mouth, as if to hold back a gasp.
"It is... Indeed ridiculously simple..." exclaimed she after a few seconds.
The detective was about to say something else, when the high school student interrupted her in her impulse.
"Wait... that would mean that the person I saw and who was arrested was a complete stranger? Who didn't even live there?" He questioned. "Is that how he got in, then?"
It was pretty logical to think that. With a security problem like that, anyone who knew that trick could get in. Still, there was one detail that bugged me. I didn't know what it was yet, but it seemed to me that something was wrong with this explanation.
The detective then shook her head, before answering him. And - this was becoming a habit - she showed once again that she knew more about the case than all of us, without revealing everything.
"Under normal circumstances, you'd think so," she said. "Only here's the thing. There's something that doesn't make sense in all of this: you saw the intruder inside Munehara-san's own apartment."
"That's... That's right... " The high school student realized. "But in that case, how did he get inside?"
The gate, pass again. But the door of the apartment? It needed a key to open it. A key...
"How come you have a key to the apartment with you?" I asked the young man.
My question surprised the detective a little, who probably didn't know in detail how I had gotten in last night. She tapped her index finger lightly on her knee, while suddenly looking at a corner of the room.
Was she annoyed? It looked like it, anyway.
From what I could see, she loved being in the spotlight.
"I found them in the owner's office," the high schooler explained, fidgeting nervously in his seat. "Most of the time, duplicate keys are kept there in a cabinet or on a board. So it was pretty easy to find them."
He had meanwhile put his colored contact lens back on, clearly uncomfortable with leaving his strange eye exposed.
"So you used the spare key to allow Nijima-kun to enter?" Asked the detective, again interested in the conversation.
In response, the high school student nodded his head.
And the detective smiled again, letting her cheek rest in the palm of her hand.
"Now, the culprit seems obvious to you, right?" She said.
Let's think about it.
A gate that was easy to break into, never being changed. Replaced locks for the window and front door of the apartment; but someone still managing to get inside.
A spare key available on the first floor of the residence, which anyone could take if they knew where it was.
And a voice that sounded familiar.
There was only one possible answer.