Yoru Sumino is a Japanese novelist who debuted in 2015 with the internationally acclaimed work I Want to Eat Your Pancreas. Sumino is a male writer currently residing in Osaka Prefecture, having begun writing during his high school years. Before his commercial debut, he initially submitted stories for the Dengeki Novel Prize but failed to pass the first round of selections. He subsequently revised his approach and wrote I Want to Eat Your Pancreas, though the manuscript exceeded the word count regulations for the prize. Seeking an audience, he posted the novel in February 2014 on the user-generated fiction website Shōsetsuka ni Narō under the pen name Yasumi Yano, where it was later discovered and led to his official publication with Futabasha in 2015.

Sumino is best known for his debut novel, I Want to Eat Your Pancreas, which became a bestseller with over 2.5 million copies in circulation. The work garnered significant recognition, securing second place in the 2016 Japan Booksellers Award. Following this success, he has published a number of other notable works. His second novel, I Had That Same Dream Again, was released in February 2016, while At Night, I Become a Monster followed in December of the same year, both with illustrations by loundraw. Subsequent major publications include I Have a Secret in March 2017, I Am Blue, in Pain, and Fragile in March 2018, and the ongoing Mugimoto Sanpo no Suki na Mono series which began in 2019.

The adaptation history of Sumino’s work is extensive and forms the core of his profile as a creator whose stories have been translated into multiple media formats. I Want to Eat Your Pancreas was adapted into a manga, a live-action film released in 2017, and an animated film which premiered in 2018. I Had That Same Dream Again was serialized as a manga from September 2017 to August 2018. I Have a Secret also received a manga adaptation beginning in April 2019. More recently, I Am Blue, in Pain, and Fragile was adapted into a live-action film released in August 2020.

Recurring themes in Sumino’s body of work include coming-of-age narratives that explore interpersonal relationships, loneliness, and the emotional growth of young protagonists. His stories frequently center on characters who carry secrets or navigate personal struggles, as seen in the hidden illness in I Want to Eat Your Pancreas, the childhood isolation in I Had That Same Dream Again, and the collective secrets of five classmates in I Have a Secret. The titles themselves, such as I Am Blue, in Pain, and Fragile and I Will Forget This Feeling Someday, often directly signal an introspective focus on emotional states and the process of self-discovery.

In terms of industry significance, Yoru Sumino is recognized as a commercially successful author whose debut marked a breakthrough for novels originating from online platforms. His work has consistently ranked highly in literary awards and sales charts, with I Am Blue, in Pain, and Fragile ranking first in the 2018 Honto Hatachi ga Ichiban Yonda Shōsetsu Ranking. His ability to generate works that are rapidly and repeatedly adapted into manga and film underscores his impact on contemporary Japanese popular culture and his broad appeal across different media audiences.