TV-Series
Description
AA2153 serves as a rookie red blood cell transporter within a deteriorating human body marked by neglect and harsh conditions. Starting his duties with enthusiasm for oxygen and nutrient delivery, he grows disillusioned amid obstructed vessels, rampant pathogens, and flooding stress hormones. His hazardous routes traverse cholesterol-clogged arteries while evading threats like bacteria and carbon monoxide.

He possesses brown hair and wears spectacles with yellow pupils, clad in the standard erythrocyte uniform bearing his concealed identification code inside his hat. Despite inherent dedication, his spirit wavers under the body's relentless decay. Key bonds include his camaraderie with fellow trainee AC1677 and protective neutrophil U-1196, who repeatedly saves him and offers solace.

His resolve initially hardens after witnessing cellular sacrifices, but AC1677's death during a stomach ulcer incident plunges him into survivor's guilt. This triggers a depressive collapse: he abandons work and courts self-destruction. His despair erupts into rebellion during a gout crisis, where he deliberately damages capillaries to protest the host's abuse. U-1196 halts his mutiny, guiding him through grief until he resumes duties as an acknowledged veteran, not a novice.

When the body stabilizes post-heart attack, his outlook brightens. Later transfused into a second, graver compromised body, he faces mockery from cynical local erythrocytes. Undeterred by escalating tragedies, he rallies the cells, forging a partnership with neutrophil J-1178—dubbed "White Blood Cell-chan"—and emerging as a red blood cell leader. His zeal sometimes spirals into overwork, necessitating reminders that survival hinges on shared labor, not solo martyrdom.

In live-action, his arc embodies the "BLACK" narrative, intersecting with AE3803 post-transfusion. His journey charts an evolution from fervent newcomer to a tenacious figure nurturing hope against systemic ruin.