Chapter 1: The Jade-Eyed Transfer Student
The June rain pattered gently on the roof of the old school building. A humid breeze slipped through the cracks in the windows, bringing a faint musty smell to the hallway. The hydrangeas in the schoolyard showed off vivid gradients of blue and purple beneath the overcast sky but even their colors seemed cold, shrouded in a heavy, dull atmosphere.
Inside the classroom, everything seemed normal: desks lined up by the windows, posters for the school festival on the walls, the scent of textbooks. Yet something was off. A tension hung in the air, one that Ao Kamizawa could clearly sense. While pretending to read the paperback in front of him, he was secretly watching the subtle shifts in his classmates’ glances.
"Starting today, we have a new classmate joining us. This is Hisui Shirasaki."
With the teacher’s announcement, the atmosphere in the room shifted. A quiet rustle rose, like a heavy metallic echo ringing in the distance. From behind the door entered a girl, gently holding the collar of her white shirt. Her black, glossy hair was neatly tied back, her skin smooth like porcelain, and her presence was striking. But her jade-colored eyes clear like gemstones held an unusually sharp glint.
"I'm Shirasaki. Nice to meet you."
Her voice was calm and cold. Yet there was a firm strength to it, giving off an odd pressure, as if she were trying to seize control of the classroom air itself.
“Well then... how about you take the empty seat next to Kamizawa. Kamizawa, help her out, will you?”
Startled by the sudden mention of his name, Ao flinched slightly. He quickly closed his book and pulled out the chair beside him. Whispering voices floated through the classroom.
"Her eyes... they’re really jade-colored."
“She seems kind of scary…”
Ao ignored the murmurs and scooted the chair over a bit to make room. Hisui sat down quietly. Her profile glowed faintly in the pale light, her expression shadowed, hiding something behind its beauty.
Ao Kamizawa was a second-year high school student. Influenced by his doctor father, he had a deep interest in medicine. After school, he didn’t join any clubs; instead, he buried himself in medical textbooks and pharmaceutical journals in the library. Though somewhat of a loner in class, he took pride in his unmatched knowledge.
To him, Hisui was like an unknown chemical compound, something he believed would not react with him.
But that afternoon, deep in the dim library, in front of the pharmacology section, he found her.
“…Ah.”
“You use this shelf too, huh?”
She looked up at Ao while still holding open the book: The Borderline Between Poison and Medicine, a dense, professional volume far beyond a typical high schooler’s level.
“That book…”
“It’s fascinating. Poison isn’t just something terrifying. Depending on the dose and use, it can become a cure.”
“That’s Paracelsus’ quote. ‘All things are poison, and nothing is without poison. Only the dose makes a thing not a poison.’”
Hisui smiled faintly. A smile shared only between those who hold the same secret.
“You’re Ao, right?”
“Yeah. Kamizawa Ao.”
“Call me Hisui.”
From that moment, their bond deepened quickly. But around Ao, a creeping sense of unease was starting to take form.
A few days later, a senior collapsed in the nurse’s office with high fever, vomiting, and hallucinations. Tests revealed an unusual substance: a trace amount of atropine derivative, a neurotoxin found in deadly nightshade. Not enough to be fatal, but clearly not accidental.
Ao quietly asked the school nurse:
“Was the student from our school?”
“Yes. Someone mentioned they smelled herbs before he collapsed.”
“Atropine… that’s found in belladonna, right?”
He remembered the faint dried herb scent from Hisui’s bag, the flicker in her jade eyes.
What does she know? What is she hiding?
That evening, at a run-down café near the station, they sat face to face.
“My mother was a traditional herbalist. But one day she was arrested for poisoning a patient. The evidence was vague, but there were flaws in how she handled her medicines. Since then, people call me the ‘daughter of poison.’”
Ao’s breath caught.
“Are you… using poison at school?”
“No. I’m not. But… someone else is. Someone who knows poison like I do.”
Their resolve was set: Ao with his knowledge of medicine, Hisui with her understanding of poison. Together, they began to uncover a darkness hidden within the school.
