Jiromaru Takaba is the younger brother of Ryo Takaba, living a nomadic existence where the siblings often camp in wilderness settings and demonstrate considerable self-sufficiency. His speech is distinctive, marked by the frequent use of "desu" and the unique term "anchan" when addressing his older brother.

Physically, he stands 115 cm tall, weighs 23 kg, and has brown eyes paired with shoulder-length brown hair. His typical outfit consists of a pink shirt, gloves, and brown boots. Born on March 25th, he is an Aries with blood type B and enjoys cooking as a hobby.

In mini 4WD racing, he pilots the "Jiromaru Special," a car sharing design elements with his brother's Tridagger X. His racing tactics include an early incident of constructing an unbalanced track to disadvantage rivals Retsu and Go Seiba, though they defeated him regardless; his car often sustains race damage. He temporarily fills Ryo's position on the TRF Victorys team during the World Grand Prix (WGP) season following Ryo's leg injury.

His relationships are defined by deep admiration for Ryo, whom he closely follows. An initial rivalry with the Seiba brothers, featuring frequent mock arguments and competition primarily with Go, gradually evolves into mutual respect and friendship. This leads to his integration into the TRF Victorys alongside them.

Jiromaru appears in the original series and WGP, though his narrative presence diminishes after his introduction as the story shifts focus toward Ryo. Concrete details regarding his involvement in MAX, Return Racers, or film adaptations are not provided in the available materials.