Eizou Hakamachi is a central figure in the anime 'Cells at Work! Code Black', a dark spin-off of the popular franchise. As an adult Red Blood Cell, Eizou stands out due to his somewhat worn and aged appearance, hinting at years of service and hard work. In contrast to the usual cheerful Red Blood Cells, Eizou is more cynical and pragmatic, often facing the harsh realities of the human body with a grim determination. Despite his critical approach, he is deeply caring towards his fellow cells, especially his partner, White Blood Cell Kurokuro. Eizou harbors a personal ambition to keep up with the hectic pace of the human body, which can be both chaotic and unpredictable, often putting his life in danger. His daily routine involves dealing with injuries, infections, and pathogens, all of which make him a crucial player in maintaining homeostasis, albeit in a more mature and subdued manner.