Jabao Jaba functions as Honmaru Edojo's principal childhood bully. He possesses an obese physique, an unattractive appearance, and consistently poor academic performance mirroring Honmaru's own struggles. Despite his weight, he exhibits significant muscular strength, delivering powerful punches. His behavior centers on physically assaulting Honmaru and venting anger upon him, including during rare instances when Honmaru attempts assistance.

His antagonistic role shifts with the arrival of powerful transfer students like Tsutomu Harako and later the Zakenja twins, who surpass him in strength. This change reveals an underlying cowardly nature previously concealed by his dominance over Honmaru. Though characterized by a violent temper, deeper narrative elements suggest a latent concern for his closest classmates.

Following elementary school graduation, Jabao attends the same local public junior high school as Honmaru and Rui Ijigawa. He is later present among the group gathered at New Tokyo International Airport to bid farewell to the departing Zakenja siblings. This continuity indicates his sustained connection to the core social circle despite earlier conflicts.