Even if Kokoro is not going to agree to it, Ai has decided to accept Yuina's advice. After they return to the classroom, Ai stands in front of the class, and she reveals the truth to everyone in Class 1-1.
When the whole class is overwhelmed in shock, Yukimuro-sensei seems pretty calm, yet concerned. It seems like Yukimuro-sensei knew it all along.
"Ai-chan, didn't you promise to keep the secret?" as Yukimuro-sensei said, she frowns and holds her tears.
While Ai shakes her head in tears, "I'm ready to bear every punishment..." she mentions, "Onechan was taking all the blame in our class, and outside of the class, Yukimuro-sensei is taking all the blame. Onechan and Yukimuro-sensei have suffered all the grievances, but I live as if nothing happened, I feel sorrowful..."
"Ai-chan..." patting on Ai's back, Yuina called softly. She wanted things to be on the right way, she feels pleased that Ai has the courage to make it right.
Whereas for the rest of the class, they do not seem pleased at all. Noises of chide covers the whole classroom in an instant.
"So it wasn't Kokoro, it's Tomori Ai..."
"Which drama are you sisters acting? Who's words do you want us to believe?"
"Never thought Ai-chan would be the one so filthy!"
"Both of the sisters are dirty buta-onna!"
Loud noises continue to echo.
"Ai is the one having affair with Murakawa-kocho, why did Kokoro take her part since the beginning?"
"Kokoro has been cast aside for so long, she was wronged!"
"We have been protecting Ai-chan for so long! But it turns out the victim has always been Kokoro!"
Listening to the harsh words they used against her beloved sister, Kokoro's face covers in tears, "Please stop..." she cries and begs, "Don't treat Ai-chan like this..."
"Onechan, I'm fine..." while Ai pushes Kokoro away, "I will take it, this is my responsibility since the beginning..."
"But..."
There, Yuina points at the class, she rebukes, "Now you've known the truth, you should apologize to Kokoro-chan."
The class does it as they should, "Gomennasai, Kokoro-chan!"
"Gomennasai, Kokoro-chan!" while there are still some mean classmates, "Let's bully Ai-chan together!"
As they said, the whole class is covered in laughter, deafening, they sound so sharp, they are not just hurting Ai, but they also hurt Kokoro, badly.
Then, a girl suddenly mentions, "Since Kokoro has cleared her name, now, should we clear Yukimuro-sensei's name too?"
The others follow, "That's right! Yukimuro-sensei is innocent!" just like they are protesting against the lies.
There suddenly, a girl stands up and leaves the seat, "I can't stand it anymore, I will go tell everyone in the school now!" she walks to the front door as she said.
"Me too!" a boy follows.
"Wait for me!" the rest of them follow too.
However, just as the class is being united in this matter, Kokoro, who was just weeping in sorrow, suddenly stops crying as she hears the classmates saying something about telling everyone the truth. Her tears stop as abrupt as the faucet is tightly turned off. She dashes to the door and stands right in front of it. She opens her arms wide and blocks before the door, preventing everyone from walking out of the classroom. Kokoro who is always soft and gentle, now, her expression changes, in her eyes, they see wrath, brutality, and persistence. She stares ferociously at her classmates, just like she has become a different person. Everyone is overwhelmed in astonishment, none of them dares to make a sound.
While there, a brave boy suddenly steps up, he points at Kokoro and warns, "Step aside, Kokoro. You've cleared your name, but Yukimuro-senseri hasn't."
However, Kokoro insists. She clenches her fists and stares straight at the boy, "Anyone who knows the truth... None of you is going to leave this classroom!"
Feeling a few hands pushing on her back, Yuina is suddenly pushed out to the front of the crowd. Yuina has no choices, she could only try to approach carefully, "Kokoro-chan, what are you doing?" she asked.
Ai covers her mouth, she weeps as she begs, "Onechan, please don't be like this..."
However, Kokoro turns more aroused, "Yuina-chan and Ai-chan too!" she yelled, "No one leaves the class!"
While a girl from the crowd dashes to the front, she yells back at Kokoro, "Let me out! I want to tell everyone how filthy this bitch, Tomori Ai is!"
As she yelled, she pushes Kokoro onto the door, a loud bang is heard, everyone thought Kokoro would give up and let them be. However, unexpectedly, as Kokoro is pushed near to one of the student's desk, she inserts her hand into the drawer and draws out a viola bow from it. It was Yuina's.
As swiftly, Kokoro raises the bow high, and by the next moment, she stabs it down into the girl's neck. The girl's neck is cut open, warm blood slips down her body and drips onto the floor like manjushage blooming, one after another.
As everyone in the class is screaming in terror and running to the deepest corner of the classroom, Kokoro slowly pulls the bow out of the girl's neck. She raises the bow covered in blood and points it at the rest of them.
She opens her eyes wide and stares at them, once again, she gives her warning, "Whoever tries to walk past this door, I'll kill."
Meanwhile, just as the atmosphere in the classroom turns denser and denser, Shinji cranes his neck out and takes a peep at the scene from under the teacher's table. He then shrinks back and hides under the table again.
"W-what should we do, Wataru?" with his voice trembling, Shinji turns to Wataru and whispers, "S-should we run away now?"
"No!" while Wataru does not think that's a good idea, "We'll get killed before we touch the door!" as he said, he grabs Shinji's arm tight to prevent him from running out from beneath the table.
Then, Shinji comes up with another idea, he suggests, "Or maybe, we can hide in the corner with everyone else?"
Yes, there's a crowd in the classroom, they can camouflage themselves by blending into the crowd of Class 1-1's students, that is probably a better idea than the previous one, but...
"No!" Wataru declines again, he warns, "Have you forgotten? That 'everyone else in that corner' all ended up missing!" he said, claiming a nod from Shinji. Wataru then comes up with a proposal, "We'll stay here and wait, then we'll seize out when Kokoro is killing everyone." he said.
Best idea, Shinji thought with a vigorous nod, while unexpectedly, as he nods, his head accidentally hit the table above his head.
"Yabai!"
In a shocking expression, Wataru immediately pulls Shinji close and grabs him tight restraining his movement, he covers his mouth with his other hand trying to prevent Shinji from making another sound. There, as both of them quiet down, they listen carefully to the outside. Just then, they heard a light footsteps walking towards them.
It must be Kokoro, this is bad, this is extremely bad. She turned insane, she will definitely kill the both of them once she comes to the front and looks down the teacher's table.
The teacher's table is sitting at the front of the classroom right in the middle, there is a little distance from the table to the door. Wataru thought the only time for them to seize out the classroom, could only be when Kokoro is standing at the exact same position as them. When the three of them are standing in the same spot, they will be having the same distance to the classroom door. There, once they are at the same starting line, when Kokoro is remaining at her position, Wataru and Shinji will run out of the table and dash to the door. Once they start running on the corridor, there is a chance Kokoro will lose them in sight. They are boys, they have longer legs, it is not a fair run, but it is the only way to break free, and Wataru is somehow certain about the success rate of his plan.
Shutting his eyes tight, Shinji tries to be calm listening to his fast heartbeat, he tries to prevent his breath from being too loud, but he is so scared, it makes him feel a little light-headed. Meanwhile, Wataru inhales and exhales slowly, trying to keep his breath down, he focuses on the sound of Kokoro's footsteps trying to figure out how far she is standing from them, because his plan is going to start, anytime.
One step... Two steps... Three steps... He can hear her moving at a slow pace, but from where she is standing, it is near, she can be here in any second, or in three more steps. There, following the rhythm of Kokoro's pace, Wataru starts the countdown.
Three... Wataru puts his index finger in front of his lips hinting Shinji to be silent, he then slowly loosen his hands over Shinji's mouth and body.
Two... Wataru grabs Shinji's hand on the wrist and gives him a firm nod, claiming one back from Shinji.
One... Wataru moves his feet out of the table and...
"Now! Izaki Shinji-kun!"
As he stands up abruptly from the floor, Wataru throws the table off their head and pushes it towards Kokoro. Shinji first dashes to the classroom door and swiftly slides the door open. When Kokoro is being held back by the table, Wataru and Shinji dash out of the classroom and run down the corridor.
Outside of the classroom of Class 1-1, the building is engulfed in darkness. Shinji and Wataru dash down the corridor without turning their heads back. While soon, they realize that they are not familiar with the structure of this Forbidden Building, especially in the dark. When they finally arrive at the end of the corridor, they find that they are stuck, it is a dead end.
"Wataru... We're doomed!"