The astronomy club was silent when Aoi opened the door.
The afternoon light entered diagonally through the tall windows, casting long shadows across the floor. From up there, the city looked smaller, calmer. As if problems were reduced to distant points of light.
Aoi set her bag down on a table and sighed.
"I'm exhausted…"
"That's normal", Reina replied, dropping herself gracelessly onto one of the chairs. "Between classes, patrols, and that weird atmosphere today… anyone would be tired."
Mio closed the door behind them carefully and went straight to the window. She leaned her back against the frame, crossing her arms, watching the sky with analytical focus.
"It was an irregular day", she said. "Too many new variables."
Reina rolled her eyes.
"You talk like we're writing a report."
"Perhaps. However, what happened last night is not something we can ignore", Mio replied.
Aoi sat on one of the tables, gently swinging her legs. For a few seconds, none of them spoke. The silence wasn't uncomfortable; it was charged with a familiarity that only time can build.
It was Aoi who spoke first, almost without thinking.
"By the way…", she said, looking at the floor. "The new guy. Haru Shimizu."
Reina raised an eyebrow.
"The transfer student?"
Mio turned her head slightly.
"A relevant topic", she admitted. "Mid-year transfers are uncommon."
Aoi hesitated for a moment.
"I don't know… he seemed normal to me."
"Ah, that", Reina interjected, resting her elbows on the back of the chair. "Now that you mention it… it was a bit strange."
Aoi lifted her gaze.
"Strange?"
"Yeah", Reina shrugged. "He stared at me for quite a while."
The sentence landed lightly, like a casual remark. But Aoi tensed just a bit, almost imperceptibly. Her fingers closed around the edge of the table.
"Stared… how?", she asked, feigning indifference.
Reina looked at her for a second and then smiled, as if she had just noticed something amusing.
"Relax, relax," she raised her hands. "He's not my type."
Aoi blinked.
"Huh?", she said a little nervously, shaking her head.
"He seems too normal to me", Reina continued. "Very calm. I might even say he's shy around girls."
Mio let out a faint snort.
"That's true", she said. "Quiet guys have never been your type."
Reina smiled proudly.
"Exactly."
Aoi hesitated, but ended up smiling too. After all, they had just met him.
"I guess so…"
Mio tilted her head, watching them.
"You've always been drawn to gallant guys", she added, in a dry tone. "The romantic, overly sweet ones who look like they stepped out of a shojo manga."
Reina clicked her tongue, amused.
"Hey! That's not entirely true."
There was a brief pause.
Aoi was the one who broke the silence, almost jokingly:
"Like the masked one from last night."
The atmosphere shifted immediately.
Reina stopped smiling.
She leaned back against the chair, crossing her arms, looking away.
"That guy…", she murmured, her cheeks red with embarrassment. "I don't know what to think about him."
Aoi remembered his voice.
The way he had spoken.
The elegant and mysterious manner in which he had withdrawn.
"He didn't seem like an enemy", she said carefully.
Mio frowned.
"Nor did he seem like an ally."
Reina pressed her lips together.
"What do you mean?", she added, without looking at them. "He acted strange, but if he fights the Echoes, maybe we could help each other."
"'Tonight's prey belongs to you…'", Mio said, almost weighing each word. "Does he see Echoes as prey?"
"Don't overthink it", Reina added, regaining her composure. "It could just be part of his charming prince act."
Aoi didn't ask what she meant. There was no need to.
At that moment, a soft light appeared at the center of the club.
It floated at eye level, like a small luminous sphere that slowly took shape: long ears, a rounded body, large, calm eyes.
"Good afternoon, girls", the creature said in a sweet voice. "I detect an elevated level of emotional unease."
"Ciel", Aoi greeted immediately, relieved. "You arrived at a good time."
"So I see", the entity replied with a slight bow. "The night patrol was successful, within acceptable parameters."
Reina sighed.
"If you say so…"
Mio straightened.
"We have questions."
Ciel rotated slightly in the air, as if adjusting itself.
"I am here to answer them."
Aoi hesitated for a moment.
"We were talking about the new boy… Haru."
Ciel's eyes glowed softly.
"I have registered his presence", it said. "There are no immediate signs of emotional distortion."
Reina shrugged.
"See? Normal."
"For now", Mio added seriously. "Statistically, students who transfer at this stage often present behavioral histories."
"A juvenile delinquent?", Reina asked somewhat nervously. "Like a troublemaker or a secret pervert."
"An interesting hypothesis, Mio", Ciel continued. "If that were the case, he could be someone who might develop a higher rate of emotional instability."
Mio nodded.
"That's what I thought."
"So you think he could turn into an Echo?", Reina asked casually. "But he seemed like a normal guy."
Ciel did not respond immediately.
"There is a probability", it finally said. "It is not significant for now, but it cannot be ruled out."
Aoi frowned, watching as Ciel and her friends began to think of Haru as a lost cause.
"But… not all troubled boys become Echoes."
"Correct", Ciel admitted. "However, we must prioritize prevention."
"What if we help him?", Aoi insisted. "If he has problems, we could help him before an Echo is born from his emotions."
The response was immediate.
"If you help one, you will want to help them all", Ciel replied. "That is humanly impossible."
The silence that followed was uncomfortable.
Mio narrowed her eyes.
"That answer is… cold."
"It is efficient", Ciel corrected. "Echoes are anomalies outside the system and must be observed and purified."
"Changing the subject", Mio continued. "We need to talk about evolved Echoes."
Reina looked up.
"Evolved?"
"The one from last night didn't react like the previous ones", Mio explained. "It resisted purification for longer. It even tried to adapt."
Aoi nodded slowly.
"How is that possible?"
Ciel remained floating in the air, listening without interrupting.
"In these three months, we've never seen an Echo do anything like that", Mio continued. "At least, not under normal conditions."
"Normal conditions?", Reina asked. "That doesn't sound very reassuring."
"It isn't", Mio replied. "If the Echoes are changing, it means something in the environment is changing as well."
Aoi looked at Ciel.
"Do you know anything about this, Ciel?"
The creature's eyes glowed just a little brighter.
"Fluctuations in Echo behavior have been recorded", it replied. "However, they are still within acceptable margins."
"Acceptable?", Reina repeated incredulously. "They almost overwhelmed us last night!"
"But they didn't", Ciel replied gently. "The system responded appropriately."
Mio frowned.
"Not exactly", she said. "If that masked warrior hadn't intervened…"
The atmosphere tensed again.
Reina pressed her lips together.
"He wasn't part of the plan, was he?"
"Correct", Ciel replied bluntly. "That entity is not part of the system."
"Entity?", Aoi repeated. "He's a person, Ciel."
"He is an unregistered factor", it corrected.
Mio stepped forward.
"Then explain something to us", she said firmly. "When we first met you, you said we were the only ones who could face the Echoes."
Aoi and Mio tensed at those words.
"How is it possible that someone else exists who can fight the Echoes?"
Ciel fell silent for a second.
It was a silence that was far too precise.
"There are multiple sources of potential energy", it finally replied. "However, only one has been authorized for purification."
"Authorized by whom?", Reina asked.
Ciel inclined its head slightly.
"By the system that chose you to purify the Echoes."
Aoi felt a chill run down her spine.
"He didn't seem like he wanted to purify it…"
"Exactly", Ciel confirmed. "And that is why he is dangerous."
Reina tapped her foot lightly against the floor.
"Dangerous to whom?"
"To the people you are trying to save."
Mio reflected for a few seconds.
"Then…", she said slowly, "is he dangerous?"
"He is interfering", Ciel corrected. "And interference generates errors."
Aoi clenched her fists.
"But if he hadn't appeared…"
She couldn't finish the sentence.
Ciel looked at her.
"In that case, the system would have adjusted the situation."
"How?", Reina asked, a thread of distrust in her voice.
"By optimizing the outcome", Ciel replied without hesitation.
The silence that followed was heavy.
Mio closed her eyes for a moment.
"Ciel…", she said carefully. "What would have happened if we couldn't win?"
"There is no point in discussing possibilities", it replied indifferently. "You must master your powers to avoid repeating a similar situation."
No one spoke.
The sun was beginning to set, dyeing the city in orange hues.
"We should get going", Mio murmured.
Reina nodded, still frowning.
"Yeah… tomorrow will be another day."
Aoi picked up her bag, but before leaving, she stopped and looked at Ciel.
"What if he appears again?"
Ciel watched her in silence.
"Then", it replied. "You will have to correct that variable."
The girls left the club one by one.
Ciel remained floating alone, watching the city from above.
The lights began to turn on, one by one, like artificial stars.
"Anomalies outside the system must always be eliminated", it whispered.
Its voice was still sweet.
But it no longer sounded reassuring.