Chūkan Kanriroku Tonegawa (中間管理録 トネガワ) is a spin-off of the Kaiji series, which follows Tonegawa, the right hand man of Kazutaka Hyōdō, the president of the Teiai Corporation and owner of numerous gambling tournaments.
After Hyōdō is getting bored with his life, he orders Tonegawa to organize a so called "game of death" as it is his and his subordinate's job to keep the president in a good mood. Tonegawa must cooperate with his subordinates in order to make the president happy and what follows is a humorous story of his interactions with his subordinates and other characters of the Kaiji series.
The series mainly focuses on the happenings inside the Teiai Corporation and has a more comedic tone to it compared to the main series. The blacksuits are also given more screen time as the series follows a few of them around their daily lives and provides names for a few.
It acts as a prequel before the events of Kaiji as some of the gambles like the Steel Frame Crossing are first seen here in their conceptual stages (albeit in a comedic way).
It should be noted that Nobuyuki Fukumoto does not do the art for the manga of this series.
- In Volume 5, there is a crossover event named "Tonegawa VS Hanchou" where Tonegawa meets Ōtsuki. Starting with episode 14, the anime also serves as an adaptation for 1-nichi Gaishutsuroku Hanchō. Coincidentally, the anime's 15th episode depicts that meeting between Tonegawa and Ootsuki.
- On a related note, Yamazaki happens to eat at the same restaurant as Ootsuki and Numakawa at one point.