Prologue: Something Finished

“Needless to say, an end comes to all things in this world. The question is whether that end comes slightly before people think it has ended, or slightly after it has been forgotten…”

The incident occurred on June 6th, between 8:00 and 9:00 in the afternoon. That was the day after Horokusa Junpei, Takanashi Nerina, Kaguyama Murasakiko, and Sazaimaru Beniko had spent the night playing mahjong at Horokusa's apartment in Avarice Heights.

The victim was strangled in her room. The room's sole door was locked from the inside. The door was on the mansion's second floor, in a position easily visible from the large banquet hall below. On the night in question, many people happened to be present in that hall (Kaguyama Murasakiko and Sazaimaru Beniko being among those). Despite this fact, not a single one of them witnessed anyone other than the victim enter or exit that door.

On the opposite side of the room was a large window, but it had also been locked from the inside. Horokusa, the detective, had been keeping watch over that window for the entire time the incident is thought to have taken place, and furthermore, his part-time assistant Takanashi Nerina had also been positioned such that he could see the window easily. They could both confidently assert that they'd seen nobody enter or exit through the window. Even so, behind the window in question, a figure other than the victim was witnessed by Takanashi Nerina. Therefore, there is practically no doubt that an unknown person was in the room, and that naturally, such a person is extremely likely to be the assailant.

However, at a glance, this incident was unmistakably unrealistic. Despite having no entrance they should have been able to use, someone had entered the room and killed the victim, plus every possible way they could have left was locked from the inside.

That alone would be enough to classify this a bizarre murder case.

But in a further surprising development, the method of killing was precisely the same as the deaths of three other women in the past three years. Once per year, following a certain strict rule, they had continued to commit these crimes.

***

Now then, this text is a narrative account of that very incident, from its occurrence to its settlement. There are bound to be sections written based on rumors or guesswork, but you can safely think of this as being mostly in accordance with reality. However, besides that obligatory tidbit of nuance to get general audiences intrigued (like for example, how one mustn't write a travel log without describing the changing autumn leaves), there will be no further illumination as to who is writing this account, as that person (in other words, me) shall be treated as a separate figure, and written about in the third person. Though naturally, it isn't hard to imagine me as one of the main four involved in the case……

***

The incident was settled after one month, however.

This is an account written after practically all of the facts about the case have been explained. In other words, that makes this a fortunate case where the conclusion is more or less prepared in advance. Being able to promise from the start the existence of a realistic conclusion (or at least, a conclusion that the vast majority of readers can be comfortable with), is the greatest factor preventing this plot from proceeding in a truly realistic fashion. That makes this an arrangement in which the reader is protected by that shield of fiction, so you can be fully at peace, selecting only the mysteries that most fascinate you, and enjoying yourself however you please. I don't know who thought up this system, but it sure is convenient.

***

Several days after the culprit who'd caused so much tragedy had been arrested, right on cue, Takanashi Nerina, Kaguyama Murasakiko, and Sazaimaru Beniko barged into Horokusa Junpei's room at Avarice Heights. Of course, this was for their monthly mahjong meet. By the way, Horokusa's room contained an obedient dog named Nelson. That dog was always sleeping. He had a habit of going for walks with Horokusa in the morning and evening, but other than that, he never left the room at all. A lazy bum who barely gets any exercise.

“Aah, poor thing.” Having finished lining up her tiles, Sazaimaru Beniko reached a hand towards her feet and patted the sleeping Nelson's head. “Horokusa, you said you're not coming back for two weeks starting tomorrow, right? Then it'd be way better if you let me take him. Compared to here, my place is way bigger, and I've even got a lawn.”

“Heck yeah, she's right, Nelson,” Kaguyama Murasakiko said while lighting a cigarette. She stretched out a leg to touch Nelson's back. “Going with Beniko would be way more fun. Hey you, don't you think he'll be happier with her?”

“No objections!” Takanashi Nerina went right along with the joke, downing a beer. “This apartment's no good for a dog.”

At that time, Nelson's owner stood up and went straight to the bathroom. After washing his hands, he absent-mindedly gazed out the window at the nighttime street.

He sneezed.

The sneeze felt relatively good. He felt a certain assurance, like “Hey, it's finally over.”

He had just yawned earlier and felt nothing, so why did this sneeze spur such thoughts, he wondered.

This had no relation to the incident.

He stretched his back, then went back to his room.

Three people's laughter filled the air.

“What's this all about?”

“Nelson, keep it a secret,” Kaguyama Murasakiko said, looking downwards.