Play through Chapter 1 in its entirety.
Players personally challenge the mysteries for a unique gaming experience
Shueisha Games announced that the episodic adventure game "Shonen Yuzou: The Season of Books and Keys," based on Honobu Yonezawa's novel "The Season of Books and Keys" (published by Shueisha Bunko), has released a demo in conjunction with the "Steam Next Fest" starting on Tuesday, October 20, 2026, at 1:00 AM (Beijing Time).
This title is a bittersweet youth everyday mystery adventure game where the high school boy duo of the library committee, Jiro Horikawa and Shimon Matsukura, tackle mysteries arising in their daily lives. The story of the original novel is presented with colorful illustrations and full voice acting, allowing you to enjoy an experience as immersive as watching a TV drama.
Full Chapter 1 Demo Now Available!
The demo currently available allows you to play through Chapter 1 "913" in its entirety.
[Chapter 1 "913" Synopsis]
Horikawa and Matsukura, spending their afternoons in the library, are visited by their senior, Mari Uragami. She brings a request to open an "unopenable safe" left behind by her deceased grandfather. Using the clue given to Mari by her grandfather—"Once you become an adult, return to this room again"—the two begin to tackle the mystery of the safe.
The story woven together by Horikawa and Matsukura begins here. Please look forward to it.
Players themselves take on the role of "Horikawa" to challenge the mysteries
In this title, scenes where the player, as Jiro Horikawa, actually solves mysteries will appear. This unique gameplay experience of directly facing and unraveling puzzles from the character's perspective deepens immersion in the story, offering a more "episodic" experience.
Whether you've read the original work or are experiencing this title for the first time, please enjoy the world of "Shonen Yuzou: The Season of Books and Keys" through the demo.
Demo Summary Video Now Live
A video introducing part of the story depicted in this title has been released.
Even players who haven't tried the demo are encouraged to get a first look at the game's unique atmosphere and the beginning of its story.
▼ Click here for the demo introduction video
Characters
■ Jiro Horikawa (CV: Urara Sawashiro)
Often entrusted with many tasks and prone to trusting others easily, but possesses sharp insight.
Since starting to date Matsukura, he somehow finds himself involved in strange incidents more often.
■ Shimon Matsukura (CV: Yuichiro Umehara)
Sarcastic and mature in her thinking. Tall and good-looking, she stands out.
Since starting to date Horikawa, she somehow finds herself involved in strange incidents more often.
■ Mari Uragami (CV: Arisa Sakuraba)
A third-year student and former library committee member, a senior known for her sleepy eyes and mischievous smile.
To unlock the "unopenable safe" left behind by his grandfather, he asks Horikawa and Matsukura for their assistance.
What is an Episodic Adventure?
This is a unique genre for this title that blends the experience of "reading" text with "watching." Look with your eyes, listen with your ears, and operate with your fingers—experience the story with all five senses, immersing yourself as if watching a TV drama, in this new form of adventure.
While preserving the lingering resonance inherent in text-based stories, the goal of this title is to allow players to experience the story with the immediacy of a visual production, savoring the subtle emotions of the characters with all five senses.
Overview of the Episodic Adventure Game "Shonen Yuzou: The Season of Books and Keys"
■ Original Work: "The Season of Books and Keys" by Honobu Yonezawa (Shueisha Bunko)
■ Supported Platforms: Nintendo Switch / Steam
■ Genre: Episodic Adventure
■ Release Date: This Winter
■ Number of Players: 1
■ Rating: Pending
■ Price: Pending
■ Languages: Simplified Chinese / Traditional Chinese / Japanese / English
■ Publisher: Shueisha Games
■ Developer: iMel Inc.
■ Copyright:
©Honobu Yonezawa/Shueisha
©SHUEISHA, SHUEISHA GAMES
"The Season of Books and Keys"
■ Nintendo Store: Scheduled to be announced soon
■ Developer Profile
iMel Inc.
iMel Inc. is a Japanese game studio specializing in the development and sales of visual novel (text adventure) games. The company excels in development using "Artemis Engine," a multi-platform game engine built specifically for visual novels, releasing titles widely both domestically and internationally for home consoles, smartphones, and PC.
■ Major Titles
"Sowing Ballad" (Development), "Lilac" (Development), "Star of End" (Steam version, mobile port development), "ATRI" (Nintendo Switch version, mobile port development and sales)
Overview of "The Season of Books and Keys"
The author is Honobu Yonezawa. He made his debut in 2001 by winning the Encouragement Prize in the Young Mystery & Horror category at the 5th Kadokawa Gakuen Novel Awards for "Hyouka." The "Classic Literature Club Series," led by "Hyouka," has been adapted into anime, manga, and live-action films, becoming bestsellers.
In 2011, he won the 64th Mystery Writers of Japan Award (Novel and Linked Short Story Collection category) for "The Broken Dragon."
In 2014, he won the 27th Shiba Ryotaro Prize for "Mangan." In 2021, he won the 12th Yamada Futaro Award for "Kokurojo," and the following year, in 2022, the same work received the 166th Naoki Prize and the 22nd Honkaku Mystery Award. "Kokurojo" ranked number one on all four major annual mystery rankings in Japan, achieving a historic quadruple crown. In 2025, he won the 10th Yoshikawa Eiji Bunko Award for the "Shomin Series."
The novel "The Season of Books and Keys" is the first installment in the "Library Committee Series," which has sold over 400,000 copies. The second installment, "The Season of Shiori and Lies," is also available to great acclaim.
※ All images shown are from work in progress.
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