Kamen Rider Kaixa appeared in the series Kamen Rider 555 and every year, the actor who portrayed Masato Kusaka/Kamen Rider Kaixa, Kohei Murakami (村上幸平), holds a special event for fans. September 13 is also known as “Kaixa Day” due to the number version of the date: 9-13. 9-1-3 is the number sequence Masato Kusaka used to transform. It was announced that the character would have a manga spin-off.
The series will be written by Toshiki Inoue (井上敏樹), who wrote Kamen Rider 555 with Kanoe Yuushi (かのえゆうし) in charge of the art. Murakami is also in full participation with the project.
Kamen Rider Kaixa: Kamen Rider 913 is scheduled to debut in Dengeki Maou in November 2019, which will be released on September 27, 2019 for 700円. TTFC paid members can also read it on their app. It will be in a seperate booklet. The booklet will also include comments by Inoue and Murakami.