The next day, Gabriela decided to find out more about the pendant found behind the music building.

She made her way to the school's broadcast room during break. The small room was full of simple broadcast equipment and was guarded by an officer named Pak Agus. Gabriela knocked on the door, and Mr Agus lifted his face from the pile of papers he was examining.

'Can I help you, Gabriela?' asked Mr Agus kindly.

Gabriela took out a pendant from a small pouch on her uniform and placed it on the table. 'Sir, I found this behind the music building. Can it be announced? Maybe someone lost it.'

Mr Agus looked at the pendant for a while before nodding. 'Okay, I'll make the announcement now.'

He immediately switched on the microphone and made the announcement. 'Attention all students, a silver pendant has been found behind the music building. For anyone who feels lost, please come to the broadcast room to check it out.'

A few minutes after the announcement, six students came to the broadcast room to check the pendant. Gabriela scanned their faces carefully one by one, trying to find clues.

Among them, a girl named Diana stepped forward. She picked up the pendant and examined it carefully. With a confident tone, she said, 'This is mine! I lost it two days ago.'

Gabriela frowned. 'Are you sure it's yours? How did it get lost behind the music hall?'

Diana nodded firmly. 'Yes, I'm sure. I even remember the details of the engraving.' She pointed to the small part on the back of the pendant, where the initials D.R. 'I think this pendant fell out of my bag when I passed that area.'

Gabriela nodded, but there was another question pressing in her mind. She hesitated for a moment, then asked, 'Diana, do you know anyone named Catherine?'

Diana looked puzzled at the question. She shook her head. 'Catherine? No, I don't. I don't know who that is. Why do you ask?'

Gabriela tried to read Diana's expression, looking for signs of a lie, but found nothing. The girl looked completely clueless.

'Oh, it's okay. I'm just curious,' Gabriela replied, forcing a smile.

Diana put the pendant in her pocket. 'Thank you, yes, Gabriela. If it weren't for you, this pendant would have been lost forever.'

'No problem,' Gabriela replied. She was smiling, but her mind was racing.

After Diana left, Gabriela sat in the broadcast room chair, trying to put the pieces of information together in her head. If the pendant was Diana's, why was Catherine associated with the place? Or maybe the pendant had nothing to do with it at all? But why did Catherine keep appearing there?

These thoughts made Gabriela even more confused. She felt like she was trying to solve a puzzle without having all the pieces. However, one thing she was sure of: Diana didn't seem to be hiding anything. The girl's expression was completely honest, and there were no signs that she was related to Catherine or her death.

Gabriela let out a long breath. In that case, this pendant was not a clue.

However, in her heart of hearts, she knew that something was still hidden in this school that might be the key to uncovering what really happened to Catherine.

The bell that signalled the end of the lesson rang, filling the classroom with the noise of students rushing home. Gabriela remained sitting pensively, her gaze blankly on the desk. Lisa, who was packing her bag, noticed Gabriela.

'Why, you look strange,' Lisa asked in a concerned tone.

Gabriela came to her senses and tried to smile a little. 'Nothing, I was just daydreaming.'

Lisa nodded, though she still looked doubtful. 'Okay, if you need someone to talk to, let me know. I'm going home first.'

After Lisa left, the room fell silent. Gabriela was the only one left, sitting alone in the classroom. The air-conditioning that started out cold slowly turned warm, even stuffy. Gabriela looked up, feeling something strange. Before she had time to think further, a heavy yet hoarse voice came from behind her.

'I know... I remember...'

Gabriela gasped, her head turning quickly. Catherine's spirit stood there, her eyes full of anger and despair.

'What do you remember?' Gabriela asked in a hesitant tone, her voice almost a whisper.

'Someone hit me on the head from behind,' Catherine replied with certainty, her tone cold. She looked deeply at Gabriela before adding, 'Come with me... I'll show you where.'

Gabriela felt her body heavy, as if it were seized with a frozen fear. However, curiosity and the desire to help Catherine overcame her fears. She stood up, looking at Catherine with determination.

'Okay, show me the way.'

Catherine turned, her shadow moving silently across the classroom floor. Gabriela followed her, exiting the school building and heading for the less-travelled outskirts. The sky had begun to turn red, signalling late afternoon, but the atmosphere was darker than usual.

They arrived at the back of the school, a place that looked deserted and gloomy. There, Gabriela saw something that immediately made her breath catch. The police line was still encircling a certain area, and on the tarmac there was a white line forming the silhouette of a human body where someone had been lying before being found.

'That's the place,' Catherine whispered, her voice trembling with emotion.

Gabriela stepped closer, staring at the white line with a heavy heart. She tried to imagine what had happened here, where Catherine had breathed her last. 'What happened here, Catherine?' asked Gabriela quietly.

Catherine stood near the line, looked down, then answered in a low voice, 'I don't know who did it, but I remember the pain... and how everything went dark afterwards.'

Gabriela bit her lip, her mind racing. Catherine might remember how she died, but without knowing who did it, uncovering the truth would be a much tougher task.

Gabriela tore her eyes away from the white line on the tarmac and looked at Catherine. The fading twilight made the spirit's figure look even more faint, but her face remained clear, filled with a deep sense of emptiness.

'Then, let's talk more about this on the way. You can come with me home,' Gabriela invited, her voice calm but hopeful.

Catherine shook her head slowly, a heavy look on her face, as if she was holding back a fact she was reluctant to share. 'I can't.'

Gabriela frowned. 'Why not? You can go anywhere around this school, right? What difference does it make if we go a little further?'

Catherine looked down, rubbed her transparent arms, and replied bitterly. 'There is something... something invisible, restricting me. This path... this border... I cannot cross it. Every time I try to go further, my body feels like it's being pulled back. Even if I push myself, I'll just be blown back here.'

Gabriela looked at Catherine with a mixed expression of curiosity and pity. 'You really can't get through? Have you ever tried to find another way out of here?'

'I've tried,' Catherine replied, her voice sounding tired. 'I've travelled around... tried every side that surrounds this place. But it's always the same. Something is trapping me here. Maybe it's my punishment, or... something I must complete before I can be free.'

Gabriela sighed, her brain racing for a solution. 'In that case, we need to find out what's holding you. Maybe it has something to do with the way you died or with someone connected to you.'

Catherine looked up at Gabriela, the spirit's eyes seemed empty but held a glimmer of hope. 'I don't know if it will work... but you're the only one willing to help me. I just want to know why I had to end up like this... and who did it.'

Gabriela nodded, trying to convince herself that this was the right path. 'I will help you, Catherine. But I need time to find out more. You'll have to stay here while I try to dig deeper.'

Catherine smiled faintly, a smile that only lasted a few seconds before fading again. 'Thank you... I'll wait for you here.'

Gabriela felt a new weight on her shoulders. Gazing at Catherine once more, she turned and walked away from the area, with questions lingering in her mind. If Catherine couldn't leave the school grounds, then the answer might be in that very place or among those who were still alive.

Gabriela stopped walking, suddenly thinking of something important. I don't even know what room 11 Catherine is from yet... she thought as she looked up at the darkening sky. The omission made her feel stupid, and she decided to go back to the back of the school building.

Maybe Catherine was still there, she thought.

With quick steps, Gabriela retraced the same path to the police line behind the school. It was quiet, with only the rustle of the wind rustling the leaves of the large tree in the backyard. Gabriela twisted her body, trying to look around every corner.

'Catherine?' she called softly.

There was no answer.

Gabriela tried harder, holding her breath, hoping Catherine would appear as before. 'Catherine! I need to talk again! I just realised there's something important I haven't asked yet!'

Silence. Only the wind could be heard.

Gabriela began to walk around, searching every corner of the schoolyard, even checking under the tree where Catherine was first seen. However, there was no sign of the spirit.

'Catherine... where are you?' muttered Gabriela in a disappointed tone.

Frustration began to creep into her mind. Had Catherine disappeared again? Or was the spirit hiding from her? Could Catherine be disappointed or angry?

Gabriela let out a long sigh, looking up at the darkening sky. Why is it always like this? Just when I start to find clues, everything seems to disappear into thin air.

However, despite her disappointment, Gabriela decided not to give up. Maybe Catherine will show up again tomorrow. Or maybe I should find out for myself at school. At least, I know she's a child here, and I have a few places to start asking questions.

With that thought, Gabriela walked away, this time with a renewed determination to find out more about Catherine and the mystery surrounding her death.