Mystery Novel: 'How Many More Until Forgiveness'

Seventeen years ago, we looked the other way. That was the first murder.

Synopsis

Kageyama, who has achieved success as the CEO of an IT company, invited his former classmates to his own smart villa standing on the shore of a remote lake. Among the guests was Asuka, the Madonna whom everyone admired.

A nostalgic reunion in a luxurious mansion. However, a record-breaking storm completely isolates them from the outside world, and the night turns into a nightmare. The next morning, Takahashi, who was the king of the class, is found dead in his room.

Is this an accident or a murder? As paranoia swirls, communication lines are cut, and they cannot call for help. In the minds of the cornered group, the ominous memory of a 'certain student' who suddenly disappeared from the class 17 years ago resurfaces.

The silence of that day now bares its fangs at them as a deadly judgment. In the closed mansion, confessions of guilt and new murders form a chain. Who will be the one to survive, and who will uncover the truth?

Character Introduction

• Itsuki Saeki A librarian. During his student days, he was a quiet bookworm. As the protagonist, he will challenge the mystery of this closed mansion with the calm observational eye he used to keep one step away from the center of the class.

• Asuka Saito The former Madonna of the class. Currently a renowned floral designer. Her unchanging beauty and kindness become the only hope amidst the tragedy, but...

• Riku Kageyama The host of this reunion. He was an inconspicuous presence during his student days but achieved great success in the IT business. A mysterious figure who remains unnaturally calm even after the tragedy occurs.

• Kengo Takahashi The first victim. The king of the class during their student days. He works for a major trading company, and his arrogant attitude has not changed even now that he is successful.

• Yosuke Sato The 'ghost' who holds the key to the story. A student who suddenly disappeared from the class 17 years ago. His existence seems deeply involved in the core of this incident, but everyone keeps their lips sealed regarding the details.

Prologue

It was a rainy Friday night, well past the middle of September, when I found that news article. Asuka Saito was opening an expensive bottle of wine by herself to celebrate winning the Jury's Special Award at an international floral design competition. The glittering night view of the city center blurred against the large living room window. Success. Fame. A life everyone envied. None of it could fill the gaping hole deep in her heart.

Her finger, which had been aimlessly swiping the smartphone screen, suddenly stopped.

'100 Leaders Driving the New Era [Business Edition]'

Among the face photos lined up under that headline was a man she knew. Kengo Takahashi. He had put on a little weight with age, but his smug, confident smile was not the slightest bit different from seventeen years ago.

She tapped the article. A brilliant career was listed, and memories of his student days were glorified and recounted under the pretext of tracing the source of his leadership.

'--He was the class leader even back in his student days. He was like a sun that pulled everyone along, and people naturally gathered around him. Even back then, there was never a shortage of laughter around him.'

Asuka stopped her hand holding the glass and glared at the screen. Laughter. That's right, high-pitched laughter had echoed in the classroom that day, too. Takahashi had been laughing while kicking the back of the boy who was slumped over his desk. His cronies had also been laughing, clutching their stomachs.

Asuka looked at the night view outside the window. Her face reflected in the glass looked expressionless, like a Noh mask. No, that's wrong. It wasn't just those who laughed who were in that classroom. Those who looked down. Those who looked away. And—me, who couldn't say anything and could only stand there, frozen.

September 20th, seventeen years ago. The day Yosuke Sato took his own life in his room.

That seventeenth anniversary of his death was just a few days away.

Asuka opened the address book on her smartphone. Under the letter 'K', there was a name she hadn't opened in years. Riku Kageyama. He, too, was one of those who had been holding his breath in that classroom. The man who was Sato's only friend.

She pressed the call button. After a few rings, she heard a voice that was nostalgic, yet somehow dry.

“...Long time no see. It's Asuka, do you recognize me?”

Silence followed. Eventually, Kageyama muttered, “...Yeah. There's no way I could forget.”

“I have a favor to ask,” Asuka's voice was cold and clear, surprising even herself. “Let's begin our 'atonement'.”

Chapter 1: The False Reunion

“Still, I'm surprised. That Kageyama is the owner of such a grand mansion.”

With a champagne glass in one hand, Kengo Takahashi said in an intentionally loud voice. Just like in their student days, several men and women gathered around him, wearing sycophantic smiles. Even though this wasn't a stage for them, Takahashi dominated the atmosphere in just a few minutes, acting as if he were the center of it all.

The invitation had arrived a month ago. The sender was Riku Kageyama. He should have been in my class during our second year of high school, but my memory of what he looked like or what his voice sounded like was terribly vague. And now, he was the CEO of an IT company that was growing rapidly. 'Seventeen years have passed since high school graduation, and I trust you are all doing well in your respective fields. Therefore, I have planned a reunion as follows to renew old friendships.' The venue noted in the text was his private villa, standing on a lake far from civilization.

For me, Itsuki Saeki, who works as a librarian at a public library, the invitation felt a bit out of place. During my student days, I always kept my distance from the center of the class. By immersing myself in the world of books, I averted my eyes from the cruel hierarchy swirling in the classroom. Even so, the reason I accepted the invitation might have been a tiny bit of curiosity, and—a faint hope that I might be able to change from the person who hadn't changed at all since those days.

The villa was a magnificent building, just as the rumors said. With a modern design that made extensive use of glass and wood, it framed the lake view like a painting. The interior was a fully smart home, and it seemed that everything from lighting to air conditioning and music could be controlled just by speaking to an AI assistant.

Including me, ten people in total, men and women, had gathered. Considering that the original class had about thirty people, that was quite few. Looking around at the faces, I felt a faint sense of discomfort. Here were those who had been at the top of the class like Takahashi, and the group that surrounded them. And those like me, who had always held our breath to avoid displeasing them. I felt as if only people from the two extremes had been gathered.

“Wow, Asuka! You haven't changed at all!”

Cheers erupted, and everyone's gaze turned to one woman. Asuka Saito. The eternal madonna of our class. Her graceful smile and the way she swayed her lustrous black hair made it impossible to feel the seventeen years that had passed. The moment she appeared, the atmosphere of the villa brightened up. Everyone tried to talk to her and stand next to her. Just like in those days, she returned a gentle smile to everyone, without exception.

“Everyone, thank you for coming.”

Kageyama, the host, stood in the center of the lounge. There was almost no trace of his student days left. Dressed in expensive designer wear and speaking in a quiet, confident voice, he was the very picture of a successful person. However, the light in his eyes looked somewhat cold.

The party began pleasantly. Conversations about current events and old jokes flourished, and expensive champagne was emptied one after another. Outside the window, the rain had intensified before anyone noticed. The weather forecast had said that this region would be hit by record-breaking heavy rain from tonight through tomorrow.

"It's about time we wrapped this up..." The moment someone started to say that, the entire villa shook violently, and the power went out. Screams erupted. A few seconds later, the emergency power kicked in, and dim orange light illuminated the room.

"It's okay, please stay calm," Kageyama's calm voice rang out. "There was likely a lightning strike nearby."

However, his AI assistant announced a desperate fact in an inorganic voice. "All communication lines to the outside are severed. Cause unknown. Also, according to the surveillance camera footage, the only road leading to the villa has been completely cut off by a landslide."

The lounge fell deathly silent. Beyond the glass walls, the storm was raging. We were trapped on this isolated island.

Chapter 2: The First Condemnation

The night in the isolated villa was a nightmare. No one could get a wink of sleep. Listening to the wind battering the windowpanes and the trees groaning eerily, we waited for morning, holding our breath in our respective rooms. The pleasant atmosphere from last night had vanished without a trace, leaving only raw fear and suspicion swirling in its place. The culprit is among us. That fact gnawed at our hearts more loudly than the sound of the storm.

When dawn broke and the storm quieted as if it were a lie, the desperate reality became even more pronounced. Outside the windows, uprooted trees blocked the road, and the lake had turned into a raging, muddy torrent. My smartphone still had no signal.

"...First, let's confirm everyone is safe."

Kageyama said quietly to us as we gathered in the lounge. His composed demeanor now seemed rather eerie. Everyone's face was pale from lack of sleep and fear, and they exchanged glances as if gauging each other's expressions.

"Takahashi-san hasn't come out of his room yet," a woman said in a trembling voice.

"That's just like him. He's probably still sleeping off last night's alcohol," someone quipped, but their voice was clearly laced with tension.

"I'll go check on him, just in case," Kageyama said, and a few others followed. I stood by the wall, watching the situation unfold with bated breath.

Takahashi's room was the corner room on the second floor with the best view. There was no answer when we knocked. The doorknob was locked. When Kageyama opened the door with the master key, the quiet room was revealed, along with a stifling smell of alcohol.

"Takahashi...?"

One of the people who entered the room gasped. Kengo Takahashi was lying on his back on the king-sized bed as if asleep. However, his complexion was sallow, and there was no sense of life from his slightly parted lips. An empty wine glass lay overturned by his pillow.

"Hey, wake up!" One person shook his shoulder, but his body was cold as ice. The next moment, a woman's high-pitched scream shattered the silence of the villa.

Kengo Takahashi was dead.

The lounge fell into complete panic. Some were wailing, some were doubled over against the wall retching, and others were shouting, "Who did this?" The adults who had worn social masks until yesterday were nowhere to be seen.

"Everyone, please calm down! No one touch anything in the room until the police arrive!" Kageyama's calm voice barely managed to maintain order.

I stood a little away from the center of the chaos, leaning my back against the wall. My heart was beating with an unpleasant rhythm. Was it an accident? No, that's not it. The timing is just too perfect.

Suddenly, my eyes turned to Asuka Saito. She was covering her face with both hands, her slender shoulders trembling. Everyone was worried about her, offering words of comfort. A tragic heroine. Her appearance seemed all too perfect.

I was desperately trying to piece together my memories of last night. That's right, Takahashi had been bragging during the party. 'My checkup the other day was all A's. Even the doctor was surprised at how healthy I am.' Would a man like that really die of acute alcohol poisoning from just a bottle or two of wine?

And one more thing. Asuka had brought a pot of homemade herbal tea for everyone. 'It's a special blend that helps you relax,' she had said with a smile as she handed it to each person. Takahashi must have been drinking that as a chaser for his wine.

No way. It's impossible. She, that Asuka Saito, could never be a murderer.

I shook my head, trying to dismiss the ridiculous delusion. But in a corner of my heart, a cold seed of doubt was quietly sprouting. It was so faint, so uncertain, and so hard to believe, but once it had taken root, I felt it beginning to slowly spread in the thick air of this mansion.

Our long, long day had begun.

Chapter 3: The Chain of Terror and Psychological Warfare

Takahashi's death completely shattered the thin-ice trust that had existed between us. Everyone would steal a glance at the person next to them, imagining the murderous intent hidden behind their smile. Kageyama, as the host, was the most suspected and was being grilled by everyone, but he remained unfazed, only repeating, 'The best course of action is to wait for the police to arrive.'

That night, the second incident struck us in an even more eerie way.

'Aaaaaah!'

The high-pitched scream came from the second-floor bathroom. When we rushed over, Misaki, the woman who was at the center of Takahashi's entourage, was collapsed in the bathtub. The showerhead was lying on the floor, and her wet hair was plastered against her white skin. At first glance, it looked like an accidental death while bathing.

'Electrocution...? Could it be that the villa's system malfunctioned?' someone muttered in a frightened voice. This state-of-the-art mansion itself began to feel like a giant trap trying to kill us.

But I had noticed the abnormality. The smart bathroom's control panel should have been perfectly protected against water and electrical leakage. So why? Stealing glances at everyone, I didn't miss the faint, translucent gel-like trace stuck to the corner of the panel.

The terror was not just physical death. It was slowly eating away at our sanity.

That afternoon, a message arrived on my tablet from an unknown address. It seemed to have been sent to everyone else at the same time.

'It's not my fault. No one helped me. It was dark, cold, and I was all alone.'

A short sentence. But when I realized the meaning behind those words, the lounge froze. Yosuke Sato. The moment the name of the ghost we had intentionally buried at the bottom of our memories for seventeen years was revived with vivid contours.

'Who did this...!' Kageyama shouted, and everyone looked at each other's faces.

And that night, the lounge's AI speaker suddenly broke the silence and began playing music. It was a somewhat melancholy pop song that had been popular seventeen years ago. Everyone should have known it, but no one could remember the title.

'...This song...' Asuka whispered in a trembling voice. 'The song Yosuke was always listening to alone on the rooftop...'

Everyone gasped at her words. It was as if Sato's ghost were wandering through this mansion, speaking to us.

"Stop it... please, stop it...!" One man clutched his head and screamed, collapsing on the spot. Fear had reached a critical point. It wasn't just the fear that they might be the next to be killed. It was a primal fear that the sins they had desperately tried to forget were about to be exposed.

The culprit knows our hearts inside and out. And it was as if they were enjoying not just killing us, but digging up our sins one by one and driving us into a corner mentally.

I moved away from the confused group and stared into the darkness outside the window. This is not Sato's curse. It is a crime committed by human will, more calculated and more cold-blooded. And the culprit is accurately measuring the weight of our sins.

When I returned to my room, I searched for the villa's blueprints on my tablet. They had been released in a feature article when Kageyama was covered by the media as a successful entrepreneur. The electrical panel, the communication system, and... the ventilation system.

The ventilation vent in the bathroom, which was the scene of the second crime, was connected to a certain room. Asuka Saito's room.

No way. That can't be. Even so, my fingers were unconsciously typing her name and the keywords "plants" and "poison" into the search bar.

Chapter 4: The Silent Confession

"This is Yosuke Sato's revenge."

The next morning, I spoke quietly to the haggard faces gathered in the lounge. A few people flinched at my words. A name that no one had dared to speak for seventeen years. I could feel the air in the room creak under the weight of that name.

"I don't intend to say anything unscientific like it's a curse. The culprit is among us. And that person knows everything we did to Yosuke Sato."

I had spent the night organizing all the information, using the research skills and memory I had cultivated as a librarian. Takahashi's allergy, the gel-like residue in the bathroom, and the definitive evidence.

"Last night, I looked up the past design documents for this villa. And I remembered our school anthology. The poem Sato had written himself, tucked away in a corner of the literature club's collection."

I took out my tablet and displayed the digital data of the old anthology on the screen. It was something I had found in the library database, using my position as a librarian.

"The title of the poem is 'The Invisible Chain'."

I began to read the poem in a trembling voice.

"The King dies from a nut. The Princess bathing is struck by lightning. The Jester drowns while laughing. And I fade away in silence."

The lounge fell deathly silent. The King dies from a nut—Takahashi, who had a nut allergy. The Princess bathing is struck by lightning—Misaki, who was electrocuted in the bathroom. The poem had predicted the murders that occurred in this villa seventeen years ago.

"Someone is using this poem as a blueprint to commit these crimes," my voice was surprisingly calm, even to me. "Perhaps we are all the 'sinners' who appear in this poem."

Those words were the trigger. The dam broke.

...I was just watching...! The first to speak was one of Takahashi's cronies. "Even when Takahashi and the others locked Sato in the gym storage room, I was just standing there...!"

That broke the dam, and one after another, everyone began to confess the sins they had kept locked deep within their hearts for seventeen years. Hiding textbooks. Throwing indoor shoes in the trash. Scribbling tasteless graffiti on desks. And then, pretending not to see those things. Laughing. Looking away so as not to get involved.

Small acts of malice and countless silences. The fact that these things piled up and robbed a human being of their dignity, their future, and their life was now, belatedly, being thrust upon us.

Everyone was crying, begging for forgiveness, and repenting for their own sins. I was one of them, too. I had once seen Sato being beaten alone from the library window. I pulled the curtains and escaped into the world of books. I pretended I didn't see it. My silence, too, was one of the sharp blades that killed him.

Amidst the storm of repentance, only one person, Asuka Saito, sat quietly with her head bowed. There wasn't a single tear on her beautiful face.

As I listened to everyone's confessions, I was fitting the final pieces together. Someone who knew of the poem's existence and could recreate it. Someone who accurately understood Takahashi's allergies and could trigger them with knowledge of specific plants. Someone who was well-versed in the state-of-the-art villa system and could make it look like an accident. And above all, someone who knew all of our sins and believed they had the right to judge us for them.

There was only one person who met all those conditions. I stood up slowly, walked through the sobbing people, and stood in front of her.

"It was you, wasn't it, Asuka?"

Chapter 5: The Madonna's Mask

At my words, the sobbing in the lounge stopped abruptly. Every gaze that had been confessing sins and begging for forgiveness was now fixed on the one woman standing in the center. Asuka Saito. Our eternal Madonna.

She slowly raised her head. From her expression, sadness, fear, and confusion had all vanished. It was as if she were peeling off an exquisite mask, one layer at a time. What appeared at the end was a smile as cold as ice and infinitely serene. That smile spoke more eloquently than any harsh words that my deduction was the truth.

"That's enough, Saeki-kun."

Before Asuka could open her mouth, Kageyama stood in my way. His eyes, as if the calmness he had shown until now was a lie, held a fanatical light.

"You have no right to judge her."

Kageyama began to tell everything. That he had been Sato's only friend. That as the bullying intensified, he had betrayed Sato out of fear and become a bystander. That he had been tormented by that guilt for seventeen years. That Asuka, who had appeared before him, was his only salvation and his goddess.

"I only prepared this stage. A stage to clear Sato's regret and make everyone admit their sins. She is a saint who will even settle the sins I have committed."

Kageyama's confession was like a painful prayer. Knowing that Asuka's plan was murder, he had chosen to become an accomplice out of his twisted love for her and his own guilt.

"I'm no saint."

Asuka's voice echoed quietly through the lounge. She stood up and looked at each of our faces, as if appraising our souls.

"I am the same as you. No, I am a sinner even worse than you all."

Her monologue began. It was not the roar of an avenger, but the solemn oracle of a shrine maiden who had spent seventeen years listening to the voices of the dead all by herself.

"Since that day, there hasn't been a single day that Yosuke hasn't been with me. While you all forgot the past, built careers and families, and found happiness, my time remained frozen in that classroom."

Her gaze turned to the sofa where Takahashi had been sitting. "I didn't kill Takahashi because he bullied him. I killed him because he forgot the ugliness of what he had done, replaced that cruelty with words like 'leadership,' and used it as fuel for his success. I thought that callousness was killing Yosuke a second time."

Next, she shifted her eyes to the chair where Misaki had been sitting. "I killed Misaki because she was laughing. At a small gathering a few years ago, I heard her laugh and say, 'Thinking back on it now, Sato was pretty funny, wasn't he?' To you, Yosuke's despair is just a funny story once time passes. I simply could not forgive that."

Asuka slowly looked around at us. "But you know, the real sin isn't the violence itself. It's the atmosphere of this place that allowed it. Your silence, watching while pretending not to see. Kageyama's silence, betraying a friend. And... my own silence, unable to help the person I loved and thinking only of protecting my own position. We all killed Yosuke."

Saying this, she took a small glass bottle from her dress pocket. Inside, a single beautiful purple flower was soaking in liquid. Monkshood. Her knowledge as a flower designer had selected the most efficient method of death.

"This is the final ritual. I will make you all confess your sins, and then I will judge myself, the most sinful of all. With this, I can finally go and apologize to Yosuke."

Asuka reached for the cap of the bottle. That was the moment.

Epilogue: Unfading Sin, Continuing Atonement

"Stop!"

My shout and one of the people kneeling on the floor breaking down in tears, saying, "I'm sorry... I'm truly, truly sorry...!" happened almost simultaneously. That voice was contagious, and the lounge was filled again, but this time with voices of genuine apology and regret. It certainly shook Asuka's heart for a moment.

That brief moment of hesitation. As if threading through that gap, the heavy sound of propellers echoed from afar. The storm had passed, and a rescue helicopter was approaching the lakeside, which had regained its silence. The time-locked distress signal that Kageyama had set had been activated.

The small bottle slipped from Asuka's hand. Her ritual ended without being completed. She did not resist and was taken into custody by the police officers who had arrived with Kageyama. We left the mansion of nightmares, illuminated by the rescue team's lights.

One year later. The incident caused a great stir in society as the 'Lakeside Villa Serial Murder Case.' We survivors had our privacy exposed in an amusing way by the media and were branded with the digital tattoo of 'bystanders to bullying.' That was the punishment meted out to us by society.

Under the clear autumn sky, I stood before Sato Yosuke's grave. One by one, the other survivors from that villa arrived. Everyone looked much older than a year ago, with tired faces.

"We've established a fund," someone said. "A small fund to support NPO organizations working on bullying issues. This is all we can do."

Sins never disappear. We will live the rest of our lives carrying this burden. But rather than just living in hiding, we will face those sins and do something for the future. That was the only form of atonement we could find.

When we all put our hands together and were about to leave the grave, I noticed a single flower placed at the base of the tombstone, different from the ones we had offered. It was a purple, elegant anemone. The flower language is, 'I believe in you and wait.' And another meaning is—'Forsaken.'

It was the flower that Asuka, who had been a flower designer, said she liked the most. I don't know who offered it. But that single flower seemed to indicate that the incident, which should have ended, was still quietly and eternally continuing in someone's heart. Quietly telling us that our long, long road of atonement had also just begun.