A forensic toxicologist and a detective team up to solve cases of "everyday poisons." Debut work by Naji Takatsu, winner of the 2025 Sosaku Grand Prize Kobunsha Award, finally published.

Naji Takatsu's work, which won the Kobunsha Award at Japan's largest creative contest "Sosaku Grand Prize 2025," has been made into a book. "Houdoku Gakusha: Ietatsu Rui" (The Forensic Toxicologist: Rui Ietatsu), revised from the award-winning piece, will be released by Kobunsha on July 8, 2026 (Wed).

Purchase here: https://www.amazon.co.jp/dp/4334110738

A popular female chef suddenly dies while out one day. The cause of death was a heart attack, and it was supposed to be a low-suspicion case. However, due to the victim's prominence, the First Investigation Division and the private research institution C.E.L.L. (Cell) decide to investigate. At Cell, who partners with the police, is the eccentric forensic toxicologist Rui Ietatsu. This is an unpredictable poison mystery where a male-female buddy duo unravels cases involving "poisons" found in everyday life.

Pages turn without stopping. Naji Takatsu's striking debut work leaves you wanting more. Please pick it up and take a look.

Comment from author Naji Takatsu

I thought, "Let's try writing this seriously for once," and packed this work with my favorite elements.

The interesting thing about the Sosaku Grand Prize is that people other than the judges can read it.

I applied thinking, "If I apply and someone says my work is interesting, then that person is a friend who finds the same things interesting as I do. Let's find friends." To my happy surprise, Kobunsha was the first to reach out and take my hand as a friend.

- Poisons - Male-female buddy duo - Richly characterized individuals

If any of these words resonated with you, you are likely a friend.

I hope to deliver a reading experience that makes you "addicted" to the work, unable to leave its world even after finishing, and wanting to meet the characters again, to as many friends as possible.

▼ Award-winning work "Doku no Koe ~Houdoku Gakusha Ietatsu Rui no Jikenbo~" (The Voice of Poison ~The Case Files of Forensic Toxicologist Rui Ietatsu~) is here

https://tales.note.com/723_takatsu/wr6bnzex512b4

Comment from the Editor in Charge, Kobunsha Bunko

Ms. Takatsu was the only recipient of multiple media awards at the Sosaku Grand Prize 2025. At Kobunsha, we unanimously selected her for the media award due to her high writing ability and the story's appeal.

This work is a story where a male-female buddy duo solves cases using everyday poisons. It incorporates surprising developments, from ancient poisons like fugu toxin to cases involving new poisons like data poisoning, making you exclaim, "There are such poisons...!". The "more than colleagues, less than lovers" relationship between Rui and Kujo is also a charm, making you imagine their future. It is a work that offers a rich reading experience both as a mystery and as a human drama.

There are already ideas for a sequel, and serialization is being considered. Many people might wonder, "What is forensic toxicology?" but we encourage them to pick up this book and immerse themselves in Rui's world.

Author Profile

Naji Takatsu (たかつ なじみ)

Born in Tottori Prefecture. Won both the Kobunsha Award and the Amuse Creative Studio Award at the Sosaku Grand Prize 2025. Debuted as a commercial author with this work.

note: https://note.com/723_takatsu

TALES: https://tales.note.com/723_takatsu

X: https://x.com/723_takatsu

"Houdoku Gakusha Ietatsu Rui" (The Forensic Toxicologist: Rui Ietatsu)

Author: Naji Takatsu Published by: Kobunsha (Kobunsha Bunko) Price: 990 yen (tax included)

ISBN: 978-4-334-11073-4 Release Date: July 8, 2026 Format: Bunko (Paperback) Pages: 384

Purchase here: https://www.amazon.co.jp/dp/4334110738

About the Sosaku Grand Prize

The Sosaku Grand Prize is a large-scale creative contest jointly organized by note and TALES, aiming to discover future star creators. In the past four years, it has received a cumulative total of 173,387 submissions and has realized media adaptations of 34 works, including book publications, video adaptations, serialization, and stage plays. It is a gateway to professional debut where creators and numerous media outlets gather.

https://note.com/contests/sosaku2026

Initiatives to Expand Creators' Opportunities

note is engaged in various initiatives to expand opportunities for creators. Through the "Creator Support Program," which introduces popular note creators to media partners to facilitate publishing and serialization, the hosting of diverse projects and events, and the "Job Request" tab function that allows for commissioning work from creators, note aims to become a home base for creators.

note

note is a media platform where creators can post text, images, audio, and video, and users can enjoy and support that content. We value a safe atmosphere and diversity so that anyone can enjoy and continue creating. Individuals and corporations mingle, creating opportunities to find things they like and meet interesting people. Launched in April 2014, approximately 82.09 million works have been created. As of the end of May 2026, there are 12.48 million members.

● URL: https://note.com/

● iOS App: https://itunes.apple.com/jp/app/note-noto/id906581110

● Android App: https://play.google.com/store/apps/details?id=mu.note

note Inc.

Our mission is "to enable anyone to start and continue creating," and we are building systems for expression and creation. The media platform note supports all creative activities of creators. Creators can publish their content as they wish, receive support from fans and peers through memberships, store owners and brand owners can introduce their products in stores, and corporations and organizations can disseminate information using note pro.

Location: 6-6-2 Kojimachi, Chiyoda-ku, Tokyo 102-0083

Established: December 8, 2011 CEO: Sadaaki Kato Corporate Site: https://note.jp