Mei Hachimoku is a Japanese author best known as the original creator of the light novel The Tunnel to Summer, the Exit of Goodbyes, which was later adapted into a manga series and an anime film. Born in 1994, Hachimoku is a native of Himeji in Hyōgo Prefecture and grew up in the Kansai region of Japan. The creator began writing derivative works of favorite manga and video games during high school, an experience that laid the groundwork for a professional writing career. Hachimoku made a notable debut by winning both the Gagaga Award and the Special Jury Award at the 13th Shogakukan Light Novel Taishō, a competition that helped launch the debut work, The Tunnel to Summer, the Exit of Goodbyes.

The body of work by Hachimoku is centered on a series of standalone novels that often incorporate themes of time, youth, and human connection. The debut novel, The Tunnel to Summer, the Exit of Goodbyes, was published by Shogakukan under its Gagaga Bunko imprint in July 2019. This was followed by Wait For Me Yesterday in Spring and An Autumn in Amber, a Zero-Second Journey, which are considered part of a thematic series known as Time and Four Seasons. In 2021, Hachimoku began publishing The Mimosa Confessions, a multi-volume series that concluded in June 2024. More recently, Hachimoku contributed to the broader franchise of a popular work by writing Frieren the Novel: Prelude in 2024.

The adaptation history of Hachimoku’s work began with The Tunnel to Summer, the Exit of Goodbyes, which was first adapted into a manga titled The Tunnel to Summer, the Exit of Goodbyes: Ultramarine. The manga, illustrated by Koudon, was serialized in Shogakukan’s seinen manga magazine Monthly Sunday Gene-X from July 2020 to November 2021 and was compiled into four volumes. Both the original light novel and its manga adaptation have been licensed for English release in North America by Seven Seas Entertainment. An anime film adaptation of the story, produced by the studio CLAP and directed by Tomohisa Taguchi, premiered in Japan in September 2022 and has since been released internationally.

Recurring themes in Hachimoku’s works often involve time manipulation as a narrative device to explore nostalgia, personal loss, and the complexities of adolescence. The Tunnel to Summer, the Exit of Goodbyes centers on a mysterious tunnel that alters time in exchange for a person’s life, while Wait For Me Yesterday in Spring similarly involves time travel to avert a tragedy. In The Mimosa Confessions, the thematic focus expands to include identity and LGBTQ+ themes, with the series noted for its portrayal of a transgender woman as a main character. This series ranked highly in the Kono Light Novel ga Sugoi! guidebook, indicating a strong critical reception. The anime adaptation of The Tunnel to Summer, the Exit of Goodbyes also received recognition, winning the Paul Grimault Award at the 2023 Annecy International Animation Film Festival.