New Children's Book Release: 'The Lost Item at Himawari Diner' — A Moving Story of a Girl Confronting Conflicting Emotions Over One Summer

Kumon Publishing Co., Ltd. (President and CEO: Norinori Izumi) is pleased to announce the publication of the new book 'The Lost Item at Himawari Diner' (text by Yuri Nishimura, illustrations by Ayano Ayu).

This story centers on a sixth-grade girl who helps with household chores in place of her parents, who are fully occupied caring for her sick younger brother. She struggles with feelings of loneliness and unspoken 'dark emotions' that she cannot share with anyone. While addressing the serious theme of family illness, the narrative incorporates the mystery of a lost cat—whose owner left behind a note saying 'This is a lost item'—making it an engaging read for all.

Plot Summary

'I'm a bad child. Because deep down, I wish my sick little brother would just disappear...'

Mizuki, a sixth grader, spends her summer vacation near 'Himawari Diner,' close to the hospital where her younger brother, Kazuki, is hospitalized. With her mother constantly at her brother's bedside and her father busy with work, Mizuki helps with laundry, shopping, and other household chores. She feels lonely and isolated, unable to spend time making friends, and carries emotions she cannot express.

Together with Sakurako, the granddaughter of the diner's owner, and Ren, a regular customer, Mizuki begins searching for the owner of a lost cat left behind with a note saying 'This is a lost item.' As the three grow closer, Mizuki gradually discovers that Sakurako shares similar feelings, and learns about Ren's hidden past.

Mizuki blames herself as a 'bad child' for secretly wishing her brother would vanish—until one day, she receives news that her brother's condition has worsened...

Key Features of the Book

'I wish he would disappear' vs. 'I want him to get better' — The Struggle of Conflicting Emotions

The story delicately portrays the complex and sensitive emotions of a child torn between the loneliness-driven thought 'I wish my brother would disappear' and the heartfelt desire 'I want him to get better' because she loves her family. It is a narrative that encourages acceptance of one's dual nature, sharing struggles with friends and family, and learning the importance of mutual support.

A Story of 'Illness and Family' That Empathizes with Both Caregivers and the Ill

While told from the protagonist's perspective, a key feature of this work is how it gently touches on the feelings of those living with illness through interactions with others. The presence of family and friends prompts readers to consider the emotional world of those affected by illness. On the theme of 'illness and family,' the story supports both sides and encourages deeper reflection.

An Engaging Mystery Element: 'Finding the Lost Cat' for Broad Appeal

Despite its heavy theme, the inclusion of a 'mystery element'—searching for the lost cat's owner together with friends—keeps readers turning the pages. The lost cat serves as an emotional bridge, making it easier for readers to empathize and connect, allowing even those from different backgrounds to enjoy the story.

Bibliographic Information

Title: The Lost Item at Himawari Diner

Target Audience: Upper elementary school students and up

Price: ¥1,500 (plus tax)

Format and Pages: B6 size, 168 pages

Release Date: June 15, 2026

ISBN: 978-4-7743-3965-8

Author Biography

Text: Yuri Nishimura

Born in Kyoto Prefecture. Her debut work, 'Welcome to the Omelette Shop!' (Kokudosha), was selected as a reading theme for the 59th National Children's Book Review Contest. She won the 25th Hiroshuke Children's Literature Award for 'Takkun's Morning Glory' (PHP Institute). Other works include the 'Disappearing Timetable' series (Gakken), 'Summer Vacation at the Fortune Teller's Mansion' (Kin no Hoshi Sha), and 'The Secret of Sakura Library' (Kokudosha). Member of the Japanese Association of Children's Literature Writers.

Illustrations: Ayano Ayu

Born in 2002 in Kure City, Hiroshima Prefecture. Graduated from the Graphic Design Department at Anabuki Design College after attending Kure National College of Technology. Active in various fields, including cover illustrations for children's books, opening illustrations for NHK E-TV short dramas, and newspaper advertisements. Her artistic world is deeply influenced by emotional memories from her time in Kure. Selected for the 19th TIS Open Call (2024) and the 68th Annual of the Society of Illustrators, New York (2025).