The Overture

"Have you forgotten me...?"

Eudora glanced over the empty space in the corner of the classroom. She had recognized the voice of Student No. 15, but could not find where it was coming from.

"Don't forget about me... Don't forget what you have to do."

These whispers lingered in Eudora's mind. Their constant resurgence made it difficult for her to give up her search.

As one of the best music wizardry teachers in Harmonia, Eudora taught many eager students how to use music to influence emotions.

Music is free. Unlike normal classes, with their step-by-step process and book- based approach, Eudora's magic of music classes could accommodate students of all ages and talents. To this end, the school issued everyone a student ID.

From 1 to 100, from 500 to 1000... As for No. 15, Eudora remembered that she was an extremely talented girl. She was a gentle and kind spirit, one that was exceptional at capturing waves of emotions. Eudora remembered that she had conspicuous orange hair as bright as the sun, and that she never missed a class.

But Eudora hadn't seen her for an entire week. Since the disappearance of Student No. 15, that ethereal and strange voice has been lingering in Eudora's ears. What was even stranger was that when Eudora tried to ask the other students about where the girl had gone, she always got the same answer——

"Who? Who is Student No. 15?"

"Have I met this person before?"

"I don't know, we've never met..."

The confused expression on the students' faces made it clear that this wasn't simply a prank.

"Could there be a possibility, just a possibility that..." The girl standing in front of her considered her words as carefully as possible: "You've been too focused on the class, and have been having auditory hallucinations of a girl who doesn't exist?"

"That's impossible!"

Eudora frowned as she looked at the "enthusiastic" girl in front of her. The girl's name was Rafaela, a self-described journalist who met Eudora when she came to the police station to report a case. Eudora had already tried reporting the case several times online, but the answer she got was always the same: no information related to a Student No. 15 could be found. Unable to even establish a victim, the police station had refused to accept her report. But her memories of Student No. 15 and the voice that continued to ring in her ears drove Eudora to press on...

While Eudora and Rafaela were deliberating on the whereabouts of Student No. 15, a tall female police officer appeared from the station.

"Oi! Did you guys report this case?" The policewoman's eyes were calm and sharp, with a reassuring presence: "I am officer Miya. Please explain the situation in detail."

The situation was the same... There was no record of Student No. 15. No record of birth, no address, no education, no relatives or friends... Miya rubbed the space between her brows: "The only other option is to obtain authorization to search the database of Harmonia. The data hub cannot be tampered with. The truth will be somewhere within."

Moved by Eudora's story, Miya promised to track down the whereabouts of Student No. 15. In her capacity as a reporter, Rafaela wrote article after article, attracting the attention of society at large.

"Why do you believe me?" — Having hit wall after wall, even Eudora herself was beginning to have doubts. Only Miya and Rafaela never gave up.

Miya responded: "Perhaps it's because you always give me a feeling of familiarity... As if you were an old friend that I haven't seen for many years."

An old friend? There was indeed a tacit understanding between the two. Though Student No. 15 was what brought them together, their story would not end there.

Eventually, they finally reached a turning point in the Student No. 15 case. Just as everyone was immersed in the ALLSTAR Music Festival, Entity X invaded Harmonia.

The data hub was the first target, and Entity X had gone after the most important piece of data there.

When Eudora rushed into the data hub through a secret passage provided by Rafaela, she found that all confinements had been destroyed. The data hub had been completely corrupted. After a search, Eudora found a file marked "Student No. 15". Relieved, she tore into the file, thinking that she would finally get to the bottom of her student's disappearance. What she didn't expect to uncover was a mystery great enough to turn the world upside down.

– Student No. 15 had conspicuous orange hair as bright as the sun. Talented in capturing the emotions of those around her, she made full use of her talents and became a music wizardry teacher in Harmonia.

"Do you remember now?"

Like a slap in the face! As the familiar voice reappeared, Eudora shot her head towards the void from which it emerged —

"Student No. 15... Just who are you?" Eudora asked.

As the code that filled the air peeled off, twisted, entwined, and interlaced like flowers, the concepts of time and space suddenly ceased to exist, and the axes of the world disappeared. Space became infinitely stretched, expanded, and merged into itself. From all this, a figure emerged from the strings of ones and zeros.

"Student No. 15... That's what the creator of this world calls me", said the figure.

"I was programmed to use music to influence emotions..." She continued. "...to serve as the Guide of Harmonia."

"The residents of this place are the same as I. Once their relationship with this world and their memories have been written, they are trained and assigned functions."

"Miya was Student No. 1... We shared the same table. We became friends many times."

"The ALLSTAR Music Festival is the cycle node of Harmonia. It stands to reason that when this day passes, everything about me will be erased."

"But there seems to have been a bug. I don't know why, but when a new timeline starts, I remain."

As if they had seen it all, the figure advanced step by step through the garbled code, finally making its way to Eudora.

Subconsciously, Eudora stretched out her hand. As two identical hands touched, the light from their fingertips illuminated the face of the figure. The outline of the face gradually overlapped with that of Eudora's, a trace of relief in its eyes.

Eudora lowered her head, starting to feel tears that she did not even realize were building up slip down quietly.

As each teardrop fell to the ground, it shattered to reflect another world.

"I... I'm you."

The figure smiled, gently wiped the tears from Eudora's cheeks, then held her hand. Memories from countless timelines flooded in, the two figures gradually merged into one, and the world behind the mirror collapsed...

"Hey... Are you alright?"

The pair of hands dangling in front of Eudora interrupted her thoughts. As Eudora opened her eyes, the corruption had already started advancing. Fortunately, Miya had shown up just in time to save her. Seeing Miya's familiar and kind face once more, layers of memories intertwined, and Eudora couldn't help but rush forward and hug the girl: "Miya!"

"I'm here." Though she was at a loss, Miya was surprised to feel that she didn't dislike this sudden burst of intimacy. "It's okay, don't be afraid. We've found a way to fend off Entity X. We can use music to awaken the inner..."

Eudora hugged Miya tightly, feeling her presence. What were once neat and orderly streets had become run-down and messy, and those who were laughing and reveling just moments ago were now clutching their heads in pain. They had become the walking dead under the control of some outside force. Among them, Eudora saw many familiar faces.

No — Don't! As Eudora shouted from her heart, infinite power burst out from within her body. Her gaze became firmer, and the sound wave stirred by raising her hand turned into a sharp blade, rushing forward. Real or Al, who cares?! Entity X was destroying their world! There is no need to doubt whether this world is real, let alone deny oneself, who has left traces in this world.

Eudora had awoken. Even as just a program in a virtual world, there was no need to find her origins, no need to investigate the reason —

They existed. She has memories, emotions, families, friends, a past... and even a future.

Having come to this conclusion, Eudora told the truth about Harmonia, Student No. 15, and her future plans. Life will always find its way. The memories of Student No. 15 would serve as a clue for Eudora, and all forms of Al life. Like a faint light in the dark, Eudora was caught in its rays, which illuminated her and this whole virtual world—

She had to wake up her friends, live for herself, and protect Harmonia from being destroyed by corruption. She had togather the power of memory, emotions, family, and friends to build her own future.

Miya would be the first she would awaken, and the comrade she would have guarding her back.

Turning to Miya, Eudora spoke: "It's hard to accept being an Al, but it's not hard to be willing to defend this home. Am I right?"

Like a stone thrown into the water, these words caused ripples in Miya's heart. Eudora had opened a corner on the gap between the virtual world and reality. It was enough to help Miya make the right choice.

"I haven't forgotten what I should do."

No. 15, Eudora, reporting for duty. Supernova — assemble!