The Summer Hikaru Died

Best friends Yoshiki and Hikaru have been stuck together like glue for most of their lives. Living in a small village and being the only children their age, the two boys find solace in each other's company. Their friendship seems picturesque at first glance, but Yoshiki has noticed a shift in Hikaru's demeanor ever since one fateful summer. The "Hikaru" that sits beside him now is nothing like his friend. Despite his physical appearance and memories remaining exactly the same, Yoshiki knows something is amiss and that the Hikaru he once knew is gone. When he brings this up, Hikaru partially transforms into an otherworldly being, threatening to kill Yoshiki if he cannot accept it—while also professing its love for him. Wracked with grief and unable to let go of his best friend, Yoshiki struggles to move on with his life as he finds himself getting closer to the new Hikaru. At the same time, strange occurrences begin to plague their village, bringing unsettling chaos. [Written by MAL Rewrite]

Hikaru ga Shinda Natsu won the Traditional Chinese Global Special Prize at the eighth Tsugi ni Kuru Manga Awards in 2022. It ranked first in the 2023 Kono Manga ga Sugoi! for the Male Readers division. In the same year, the manga was nominated for the 16th Manga Taisho Award and placed 11th in the final ranking. The series has been published in English as The Summer Hikaru Died by Yen Press since July 18, 2023. It has also been released in German by Altraverse since January 23, 2023; in Italian by J-POP since June 28, 2023; in Spanish by Milky Way Ediciones since March 3, 2022; and in Portuguese by Editorial Presença since August 20, 2025.