Chapter 2: Ominous Breaths
The moment the after-school chime rang, the air in the school building felt just a little lighter. That day, Ao left the classroom later than usual. He was heading toward the library when he paused at the noise coming from the corridor below the staircase.
“…A stretcher? Did someone collapse?”
A few students had gathered in front of the nurse’s office, whispering to one another with anxious expressions. In the middle of the crowd, a male student lay on a stretcher. His uniform was disheveled, his face pale, and a thin foam gathered around his mouth. His entire body was trembling slightly.
“Akiyama-senpai from the third year… He was fine just a moment ago…”
“He vomited, had a high fever, and was screaming, hallucinating, maybe?”
Ao unconsciously stepped forward, moved by both curiosity and concern, his inner “researcher” pushing him on.
The door to the nurse’s office opened, and out stepped Nurse Otonari, a stern woman in her forties. Her expression was as serious as ever, but Ao had spoken with her several times before about medicine.
“…Kamizawa?”
“Sensei, about senpai’s condition… Was it food poisoning or something?”
She glanced at him for a moment, sharp and searching.
“You know about confidentiality laws, right? But… maybe I can talk to you.”
Lowering her voice, she closed the door behind her.
“His blood work showed some unusual results. A small trace of a drug was detected in his system.”
“What kind of drug?”
“Atropine derivative. We’re still identifying its exact structure, but it’s likely natural in origin.”
Ao caught his breath.
“…From the nightshade family?”
“Exactly. For example, belladonna. It’s a toxic plant known since ancient times for its hallucinogenic properties. He didn’t ingest a lethal amount, but if he had taken just a little more, it might have been fatal.”
“It wasn’t an accident, was it?”
Nurse Otonari tilted her head slightly.
“For someone of his size, the dosage was far too high. Not something you’d consume by mistake. It was likely laced… or administered intentionally.”
A chill ran down Ao’s spine. After leaving the nurse’s office, he headed straight to the back of the library.
There she was Hisui Shirasaki once again holding The Borderline Between Poison and Medicine.
“…It’s just a coincidence, right?”
Hisui looked up, calm as ever, but Ao noticed a faint shadow in her eyes.
“What is?”
“Today, a third-year collapsed. His symptoms were… fever, vomiting, hallucinations. Tests showed traces of atropine…”
Hisui looked down and closed the book.
“I knew him. His class was next to mine. We talked a little before he collapsed.”
“Did anything seem… off?”
“There was a smell. Herbal, dry. Not strong, but something about it stuck in my memory.”
“…Atropine in belladonna. You recognize that smell?”
She paused for a moment, then nodded faintly.
“I do. When I was a child, my mother planted it in our garden. The root can be used as medicine but if you misuse it…”
At that moment, Ao remembered: a few days ago, the faint scent from the pouch Hisui had placed on her desk.
“…Hisui.”
“What?”
“Do you really… don't know anything?”
Silence filled the space between them. The air in the library turned colder. Her lips twisted ever so slightly.
“I haven’t used poison. But I know it. I know how people suffer when they’re poisoned and how to help them… Because my mother was arrested for it.”
Ao’s eyes widened.
“…What?”
“My mother was a herbalist. She treated patients at home. But one day, a regular fell ill and died. They said it was a prescription error and arrested her.”
“Was there… proof?”
“It was unclear. She maintained her innocence. But there were missing records; some herbs she used weren’t listed. That was her downfall.”
Ao’s breath caught. The past of Hisui’s mother… Only now did he begin to grasp how deeply it had cast a shadow over her.
“Since then, I’ve been called ‘poison girl.’ But I wanted to know the truth. Is poison truly evil? Or can it save someone? Who gets to decide that?”
Ao looked into her eyes. They held determination, restrained fury, and a quiet fear.
“Hisui… If someone really is using poison at this school… then let’s stop them together.”
“…What?”
“Your mother’s innocence, and everything happening now if you know poison, and I know medicine, maybe we can find the truth.”
She didn’t speak for a while. Then, slowly, she smiled.
“…Thank you, Ao.”
That smile carried a hint of sadness but in that moment, an unshakable alliance was born between them.
At the same time, in the science lab after school, someone unlocked the door to the biology prep room.
A clear liquid was being transferred to another bottle.
The next poison was already underway unseen by anyone.
