Kirigiri Novel Book 7

Final Chapter Part 2- Kyoko Kirigiri

If the rooms are not adjacent, the locked room technique does not work, and in that case— if Yui wasn't the perpetrator, only Kadomi is left.

But he undoubtedly drank the mineral water with the sleeping pills on the first day, so he was unconscious that night.

It wasn't Kadomi who killed Yukimura on the first night. And certainly not Yui.

If so, then the premise is wrong.

That locked room technique can only work if the perpetrator and the victim's rooms were adjacent to each other— that is what Kirigiri thought at the beginning.

But was it really so?

For example, what if three rooms were tilted at the same time?

The perpetrator's target was Yukimura, who was a room away from him. Usually, the perpetrator would not be able to even reach the next room because of the chains. However, if the room sandwiched between the perpetrator and the target was also tilted, so the three rooms were tilted at the same time— a path to the locked room can be formed in the air.

On the first night, Kadomi was in the middle room. But because he took sleeping pills, he couldn't even notice the tilt of the room.

Yūhain used this method to kill Yukimura.

Although it was a shortcut to the crime scene, the length of the handcuff chain should've only barely reached the target room. But it was for that purpose that the venom knife was made. As long as the window of the target's room can be reached, the rest is just pointing the knife at the victim and letting go.

No one other than Yūhain could be the perpetrator. This is the logical answer.

Nevertheless—

Why did I assume that Yui was the culprit?

Maybe this time the murder case at the Sirius Observatory was designed in such a way that whether or not Yui accepted the

'Black Challenge', she could still be considered the perpetrator. If she was willing to be the perpetrator, the 'Black Challenge' would have proceeded as planned.

If she refused to be the perpetrator— or if she accepted the role of the perpetrator but did not execute it well out of hesitation— in order to ensure the smooth progress of the plan, a pawn must be set in advance to push the case forward. That pawn was Yūhain. However, it is unclear whether he was aware that he was being manipulated.

That is the 'curse' left by Shinsen.

Why did he do such a complicated thing on purpose? Kirigiri asked the spirits.

Did he want me ruined?

Did he want me to experience the humiliation of making a major mistake as a detective?

In that case— he already got what he wanted, didn't he? Treating an important person as a criminal.

Then... killing her.

The path of reason should have been corrected at any time. The reason I couldn't do that was because... the other person was Yui.

the road I walked with her. The time I spent with her.

The places I wanted to go to with her. The things she liked.

Her smile.

She cannot be the perpetrator.

Emotions prevailed over logic.

And so— as a detective, I had to deny that. It was only natural to deny it. At the point where I started to worry like this, I may have lost my balance with reason. As a result, I failed to notice that the final answer was distorted. I took the assumption that 'she is not the perpetrator' as my emotional conclusion, and discarded it.