Over the weekend, news in Japan broke that 29-year-old Act-Age author Tatsuya Matsuki had been arrested for inappropriate contact with a minor. A Japanese middle school girl told police that Matsuki touched her inappropriately from behind. As the police analyzed security footage, it was revealed that Matsuki was involved in a second incident with a different middle school female on a nearby road.
This morning, Shueisha, the publisher of Weekly Shonen Jump has announced that Act-Age has been canceled and that the next chapter that appear in the manga magazine's next issue will be the last. While fans have little sympathy for Matsuki, there was concern for the manga's young female artist, Shiro Usazaki. Act-Age is one of the rare (yet not entirely uncommon) instances in the industry where a manga is produced by a writer and artist team instead of one person handling both writing and art responsibility.
Shueisha also released the following statement on Matsuki, which you can read below.
Matsuki Tatsuya, the writer of act-age was arrested on August 8, 2020.
The editorial department takes this situation very seriously, and after confirming the matter and discussing it with Shiro Usazaki Sensei, the artist for the series, we have come to the conclusion that it is impossible to continue with its serialization. The chapter that is in combined issue 36/37 of Weekly Shonen Jump will be the final chapter.
It is extremely unfortunate to have to end a series that has received so much support from so many readers in this way. However, this decision was made because of the nature of the incident, and because Weekly Shonen Jump recognizes the weight of its social responsibility.
Information about graphic novel volumes and related publications and events will be announced as they are decided.
Act-Age was first serialized in Weekly Shonen Jump in January 2018 and has released 12 volumes to date. With its announced cancellation, the 13th volume will be the last (though Shueisha's above statement implies that there might not be a 13th volume).
The manga series follows Kei Yonagi, a Japanese high school girl who dreams of being an actress. However, she has to raise her two younger siblings after her mother's death and her father abandons the family. Complicating matters further is Kei's incredibly immersive method-acting technique which often leaves her unable to separate herself from her role.