Makibao is a small white mule, physically resembling a donkey with notably wide nostrils. Despite this unconventional appearance compared to thoroughbred racehorses, he relies on exceptional speed and fierce determination as his primary racing weapons. His core motivation stems from his background: his horse mother, Midori, was taken from their farm to settle debts, driving his ambition to succeed as a racehorse and ultimately win her back.

He faces significant challenges in launching his racing career due to his physical limitations and initial underdog status. Makibao's journey is fueled by a fierce rivalry with the horse Superhorse Cascade, whom he is determined to defeat. He encounters numerous hardships, overcoming physical disadvantages and intense competition through perseverance and innate talent. This leads him to consistently thrive in major races, evolving from a dismissed outsider into a respected competitor who wins significant events, showcasing growth in skill and resilience.

In the spin-off "Dokodeme Makibao," he participates in unconventional races extending beyond traditional tracks. These include everyday challenges like competing for limited-edition gourmet food or environmental cleanup tasks. These scenarios depict him applying his competitive spirit and racing instincts to diverse, non-traditional contexts, maintaining his core traits of determination and adaptability while engaging in lighthearted competitions against familiar rivals.