A second season of the anime is currently in production
Frantic Anime Brief
Frantic Anime is tracking “The Summer Hikaru Died Manga Ends in 2 Chapters”. This update is filed under New Seasons & Sequels, Streaming News, Manga News. Related developments will stay grouped on Frantic Anime so readers can follow the story without leaving the newsroom.
Reporting provenance: Crunchyroll News.