Kill Blue
Kill Blue is a Japanese manga series written and illustrated by Tadatoshi Fujimaki. It was serialized in Shueisha's Weekly Shōnen Jump magazine from April 2023 to September 2025, with its chapters collected in thirteen volumes. An anime television series adaptation produced by Cue is set to premiere in April 2026.
Plot
Juzo Ogami is a 40-year-old who works for the Z.O.O. assassin syndicate as their prized hitman. During a job taking out criminals working with the genetic manipulation company Mitsuoka Pharmaceuticals, Ogami is stung by a wasp that modifies his DNA, regressing his age to that of when he was 12. Unable to resume work as a hitman due to his stature, the head of Z.O.O. gives Ogami another assignment while they work on an antidote: attend a middle school the head's daughter is applying to and judge if it is safe. Ogami, due to having no formal education, turns out to love middle school, and must balance his time as a student and an assassin. He must also deal with Noren Mitsuoka, the heiress of Mitsuoka Pharmaceuticals, who may be the key to figuring out how to age Ogami back to normal.Characters
;Juzo Ogami;Noren Mitsuoka
;Kotatsu Nekota
;Tenma Tendo
;Chisato Shiraishi
;Eri Wanibuchi
;Shin Kohazame
Media
Manga
Written and illustrated by Tadatoshi Fujimaki, the series was serialized in Shueisha's Weekly Shōnen Jump magazine from April 17, 2023, to September 1, 2025. The series' individual chapters have been collected into thirteen volumes, released from September 2023 to December 2025.Viz Media and Manga Plus are publishing the series in English simultaneously with its Japanese release. Viz Media began releasing the volumes digitally in July 2024.
Volumes
Anime
An anime television series adaptation was announced on September 1, 2025, the same day as the final chapter of the manga. It will be produced by Cue and directed by, with characters designed by Miho Daidōji. The series is set to premiere in April 2026 on TV Tokyo and its affiliates.Reception
The series was ranked seventh in the Nationwide Bookstore Employees' Recommended Comics of 2024 list. The series ranked tenth in the print category at the tenth Next Manga Awards in 2024.Kaylie Fielden of Screen Rant felt the plot was unique among other hitman manga and praised the beginning chapters. Robbie Pleasant of Multiversity Comics praised the artwork and characters. Regarding the story, Pleasant felt that it has some worrying elements concerning a possible romance between Ogami and Noren Mitsuoka but nonetheless handled them well. Kara Dennison of Otaku USA described the series as "Case Closed with added violence".