Yutaka Kōno’s I Don’t Know How to Say Goodbye Gets Manga Launch on September 26
Yukiko Seike, who adapted 5 Centimeters per Second, will draw the series for Kodansha’s Comic Days.
Sagrada Reset author Yutaka Kōno’s I Don’t Know How to Say Goodbye novels are getting a manga adaptation by Yukiko Seike. The manga debuts September 26 on Comic Days.
Sagrada Reset author Yutaka Kōno announced Friday on X, formerly Twitter, that Yukiko Seike will adapt I Don’t Know How to Say Goodbye (Sayonara no Iikata Nante Shiranai) into manga. Initially announced for fall on Kodansha’s Comic Days platform, the adaptation now has a September 26 debut date.
The novels follow Ayumu Kaya, a second-year high school student who receives an unusual letter granting him the right to become a Kamisaki resident. He has never heard of the town.
However, the envelope bears a mark he recognizes: the same one left when his friend Toma vanished two years earlier. Ayumu heads to the specified apartment building to investigate his friend’s disappearance.
The novels belong to the broader “Kamisaki” series. Kōno began the franchise with co-author Junichi Kawahashi, whose name’s romanization is unconfirmed, under the title Water & Biscuit no Theme. Kadokawa released two volumes, illustrated by You Shiina, in 2017 and 2018.
Kōno relaunched the novels alone in 2019 as I Don’t Know How to Say Goodbye. Shinchosha released volume 11 on August 28, featuring illustrations by Hagu Koshijima.
Another Kōno novel, Fragile Light of Pistol Star (Inakunare, Gunjō), received a manga adaptation by Ai Uzuki. It began in Square Enix’s G Fantasy magazine in April 2018 and concluded in 2019.
That novel debuted in 2014, opening Kōno’s “Kaidantō” novel series. Its live-action film adaptation opened in Japan in September 2019. Kōno’s Sagrada Reset novels also received a television anime and two live-action films, all in 2017.
Seike’s manga adaptation of Makoto Shinkai’s film 5 Centimeters per Second ran in Kodansha’s Afternoon magazine in 2010. Vertical, followed by Kodansha USA Publishing, released the manga in English in digital and print editions.
Sources: Yutaka Kōno 's X/ Twitter account via ANN
