At the crime scene, a young keiji comes to the old keiji in-charge of the scene.
He reports, "Sazawa-senpai, the station called, they said a patient in a psychiatric hospital has committed suicide this morning, they need us to take a look after we're done with the cases here."
Along with a deep sigh, Sazawa-keiji clicks his tongue impatiently. He turns to the young keiji and hollers, "Can't they see we are busy, Nomura-keiji? There are two corpses here in the school, one was a new teacher, one was a third year student, they were found at different places with different injuries, one was even stabbed in the chest! This is not an accident, this is a homicide case! We are trying to catch a brutal murderer here, so please tell them to send someone else!"
However, Nomura-keiji insists, "Sazawa-senpai, we have to take the case at the psychiatric hospital."
Taking a sip of his cigarette, Sazawa-keiji stares coldly at Nomura-keiji, he exhales impatiently, "Tell me why." as he said, the smoke diffuses into the air.
Waving his hand in front of his face, Nomura-keiji tries to get rid of the smoke, "It seems off, Sazawa-senpai." he mentions, "Look, the siblings were at two different locations, but they both died around the same time."
With a frown, Sazawa-keiji asks, "Nomura, you said siblings?"
"Yes." Nomura-keiji nods, "The dead teacher, Yokoyama Wataru, he had a sister, she was locked up in the psychiatric hospital since twenty years ago, her name was Yokoyama Yuina. She committed suicide four hours ago." he mentioned, holding up an old music book in his hand, "They found a music book she left under her pillow."
"A music book?"
Sazawa-keiji takes over the old music book from Nomura-keiji, he inserts the cigarette within his lips again as he opens the book. There, as he opens it, he sees words written all over the five lines stave. He frowns again, this is not a music book, this is a diary book.
On top of everything, a title is seen, 'The Disappearing Class 1-1'.
"The disappearing Class 1-1..." Sazawa-keiji mumbles, "Is she related to the mass disappearing case from twenty-years ago?"
Nomura-keiji nods, "Yes."
There, Sazawa-keiji starts to read the diary book. The first content was written twenty year ago, 1996. The content is written as below.
"Kokoro-chan, she was a wonderful friend, she was gentle and sweet, she was kind, she was always there for anyone who needed help. But one day, she went insane."
"She sewed everyone's mouth up with the viola strings I brought back from the music room, she kidnapped everyone. She buried them all in the soil of the mountain foot, including her beloved sister, Ai-chan. She let me go, and asked me to come back on the third day. She won't let me tell anyone about it."
"I was working as a part time private investigator, the director is my father's friend. I used to help him out everyday after class. The following days after Class 1-1 was killed, I stayed there every night. I am scared. I am scared that Kokoro-chan will find me, I am scared that she might want to kill me, because I am the only witness of the case, and I helped her too, I brought the viola strings back from the music room as she requested, I looked at how she sewed their mouths up."
"Two days later, a crowd appeared at the investigator firm. I heard they are searching for their children who studied in Eitsuma Middle School's Class 1-1, they were missing, they haven't been going home since Monday, on April 15th. My director was going to pass the case to my colleague, Kumamaru-ojisan, but I was concerned, I was afraid that he might find out I was an accomplice of the case, so I took over the case, and the director agreed."
"Three days after the slaughter happened, I went back to the school as promised. It was on the 18th, she tried to kill me too. She said she had been thinking for the past three days, but she decided that I need to die too. She sewed my mouth up, and she buried me on top of my classmates. But suddenly, it rained. I felt someone pushed me out of the mud. It was my classmates, I saw them, they pushed me out. So I ran, I ran to the police station for help, I tore down the viola strings and told them what happened, but they wouldn't listen to me. Soon, I was diagnosed with schizophrenia, and I was admitted to a psychiatric hospital. I was told not to ever mention anything about the mass murder again, or they will sew my mouth up like how Kokoro-chan did."
"I missed my family, my father, my mother, and my brother, Wataru. I hope I can get out of here and take a look at them, especially Wataru. I wonder if he can fall asleep when I wasn't there to play the ballad for him. Will he forget me one day?"
After this, Yuina did not write anymore, until it came to the year 2000. The content is written as below.
"The ballad, The Bell Rings on The 14th, I played it with the viola in the school every 14th since Class 1-1 was killed. I wanted to comfort my classmates' souls, I wanted to calm them down before the day they would be killed again, like how people used to sing Silent Night on Christmas Eve."
Again, the diary paused for a very long time, until it comes to this year, 2016, contents are found written in these few days. The content is written as below.
"It is the 14th of April again, it has been twenty years since it happened, but it was a little different this time. Today, I saw Wataru. I felt so happy, he has become a grown man, he is so tall and so good looking, I am so happy to see him. It was a little sad that he couldn't see me, but I know he could feel me. I held his hand and brought him to the music room. I showed him the ballad's music sheet. I wanted to hear the song, so he played it for me. I am so happy, I can't describe how happy I am, I love Wataru, I love my brother so much, I hope he still remembers me."
"Today is the 15th of April, everyone will return to Class 1-1, I missed them. Ai-chan brought a boy into the Forbidden Building, I saw Wataru again, he is here to investigate my disappearance twenty years ago. I am so happy that he did not forget me, he is always thinking of me. But unluckily, today Kokoro will be killing again, I must be there for him. I need to help them."
That was the last content written in this diary book, the pages behind are all left blank.
In front of the keiji, although they can't see them, Wataru and Shinji stand in front of them, they read the diary together with them. Wataru can't hold back but starts to cry.
"I never knew onesan was alive..." he said as he sobs, "I should have been there for her, so she won't commit suicide..."
"Wataru..." patting on Wataru's back, Shinji tries to comfort him.
Wataru turns to Shinji, he mentions, "Sorry for dragging you in, Izaki Shinji-kun. I was a teacher, I shouldn't have involved you in this case. You shouldn't have to die..."
However, just as he said, a girl's voice suddenly comes in from the behind. Wataru and Shinji turn to their back immediately.
"Wataru..."
It is Yuina, she was calling Wataru.
"O-onesan...?" looking at young Yuina's spirit, Wataru covers his mouth as he smiles in tears. He dashes to her and hugs her in his arms, "Onesan! Onesan, it's me, I'm Wataru! I missed you!"
As he said, a group of students and a teacher appear behind Yuina. Their mouths are sewed up, but they did not try to peel their mouths this time.
With a smile, Shinji greets, "Yuina-san, Ai-san, Yukimuro-sensei, and everyone in Class 1-1..."
"Shinji-kun, Wataru, thank you." there, Yuina thanked them, "You freed us."
As she said, Shinji takes a glance at his surroundings, Sazawa-keiji has ordered Nomura-keiji to get an excavator here. They are going to dig the remaining of the corpse out of the mountain foot.
With a smile, Shinji nods at them. Then, he takes a glance at his own corpse, he asks, "Are we dead?" he turns his head and looks at the Forbidden Building, "Will we be trapped here like how you did?"
Yuina first nods her head, she then suddenly shakes his head, "You have to go back. Go back to where you belong."
"No, onesan!" Wataru understands her words, but he declines, "I wasn't there for you when you're alive, I will remain here and be by your side, I'll be with you forever!"
With a smile, Yuina caresses Wataru's face gently, "No, Wataru." she said, "We will meet one day in the future, just not now. You have to go back. This is my last wish."
"Onesan..." with tears covering his face, Wataru holds tight to Yuina's hands, he is afraid to let go.
Looking at the policemen zipping the body bags up and starting to move them, Yuina reminds, "Now go, or it will be too late."
"No, Onesan!" while Wataru does not want to leave Yuina, "I don't want to leave you...!"
No matter how tall Wataru has become, he is still the younger brother. Yuina shows a warm smile and caresses his head. She gives him a last hug.
Yuina then turns to Shinji, she says, "Shinji-kun, please take care of Wataru." as she said, together with the rest of the class, they wave at them, "Sayonara." and their figures gradually faint into the lights.
"Onesan!" stretching his hands out, Wataru called in tears. While there, he finds his hand starts to disperse into the lights too.
"No! Wataru!"
Seeing them starting to vanish from the world, Shinji quickly grabs Wataru's arm and pulls him back to where his body was placed. He then lies down in the bag where his body is zipped up in.
A few seconds later, when Shinji opens his eyes again, he first takes a few deep breaths as hard as he can. He can feel his bone twisting in different directions, and he is restrained in a narrow body bag. The bag was fully zipped up, he couldn't breath. He tried to move his limbs to adjust his pose, luckily, it seems like some of his muscles are still responding. Abruptly, he sits up from the floor, claiming a sharp scream from the crowd.
"GYAAAAAAAAAA!!"
Then, a few seconds later, as he struggles, he opens the zip of the body bag from the inside. As half of the bag falls back onto the floor, Shinji rubs his eyes with his fists as he tries to adapt to the bright light of the sun.
"S-SHINJI!?" there, Shinji's friends yelled at him in astonished faces.
Whereas, Shinji turns to the body bag lying next to him. He climbs out of his body bag and comes to it. He unzips it immediately expecting Wataru to wake up right away like how Shinji just did. However, after a few seconds of waiting, Shinji finds him still dead.
"Wataru..." grabbing onto Wataru's arm, Shinji starts to cry, "Wataru!" he yells and calls his name as he shakes him vigorously, "Wataru, where are you? Come back!"
As Shinji continues to shake him, he suddenly hears a cough from Wataru. Wataru takes his first gasp of breath as he opens his eyes. He sits up aggressively and grabs onto Shinji's shoulder as he pants deeply for air. Once again, the scene shocks the crowd, some even fainted out of shock.
"Wataru!" in a face of joy, Shinji chokes in tears as he chuckles.
"Izaki Shinji-kun..." warm tears streams down his face, Wataru hugs tight onto Shinji. He leans on Shinji's shoulder and cries agitatedly.
Gently, Shinji pats on the back of Wataru's head, "It's fine, Wataru, you are fine. Don't worry anymore..."