Chūbei

Chūbei, known as "Boss," is a clever mouse from the forest who becomes the closest friend and supporter of Midori Makibaō. Their bond began when Chūbei gave Makibaō his first nickname, "Unkotarezo," after meeting him in the woods. At first, Chūbei was just having fun, but after seeing Makibaō lose to Cascade, he decided to train Makibaō seriously to help him become a champion racehorse. Chūbei always sits on Makibaō’s head during races, cheering and sometimes biting Makibaō to encourage him to run faster. He is tough, brave, and sometimes cheeky, but he has a big heart and is always there for his friends. Chūbei’s journey is full of dramatic moments, especially his final sacrifice to help Makibaō win, making him one of the most important and beloved characters in the story.

Chūbei is a small forest mouse.

He is usually seen sitting or riding on Midori Makibaō’s head during races.

Chūbei is bold, fearless, and very confident.

He doesn’t like to lose and has a sharp tongue, often making tough comments.

He can be hot-headed and acts cheeky, but he is also very caring and supportive.

At first, he seemed to play along with Makibaō just for fun, but he soon found true meaning in racing and supporting his friends.

He sometimes bites Makibaō’s head to give him a strong push during races.

Chūbei met Midori Makibaō in the forest while Makibaō was searching for his mother and had no name.

Chūbei was hiding his real identity and pretended to be a tough boss to scare and play tricks on Makibaō.

They survived a wild dog chase together, and Chūbei gave Makibaō the nickname "Unkotarezo."

From that moment, Chūbei became Makibaō’s lifelong partner and called himself the boss.

He later helped train Kansuke Yamamoto and improved the Midori Farm team.

Chūbei is not a professional jockey like Kansuke Yamamoto, but his presence is crucial for Makibaō.

While riding Makibaō’s head, he offers encouragement, direction, and sometimes even discipline by biting Makibaō, acting as a whip.

His riding skills are not perfect, but Makibaō depends on him so much that his performance drops if Chūbei is not there to support him.

Midori Makibaō: Chūbei is Makibaō’s closest partner, supporter, and friend. He named Makibaō and keeps him motivated.
Kansuke Yamamoto: At first, Chūbei competed with Kansuke as jockey, but then he decided to work together with him for Makibaō’s success.
Genjiro Obu (in the anime, Masaru Obu): Encouraged Chūbei to take a supportive role rather than leave, telling him, "cars also have a passenger seat."
Cascade: Even Cascade calls Chūbei "the greatest jockey I’ve ever known," showing deep respect.

Becoming Makibaō’s Partner

When Chūbei met Makibaō in the woods, Makibaō did not have a name and was searching for his mother.

Chūbei first acted tough to scare Makibaō for fun, but after running from a wild dog together, he decided to name Makibaō and became his boss for life.

Training and Teamwork

Chūbei decided that "Makibaō is no ordinary horse, so he can’t be raced in an ordinary way."

He felt guilty when Makibaō lost to Cascade because he pushed Makibaō too hard.

When Kansuke Yamamoto joined as Makibaō’s official jockey, Chūbei thought about quitting, saying things like "you don’t need two drivers in one car."

But after talking to Genjiro Obu, who reminded him there is also a passenger seat, Chūbei gladly became Makibaō’s co-supporter together with Kansuke.

Satsuki Sho (Satsuki Prize)

During a big match against Cascade, Chūbei tried a risky new way to help Makibaō use his special skill, the "Mustang Special."

He held onto Makibaō’s forelock, pushing his head down so Makibaō could run faster.

Right before the finish line, Chūbei fell off, causing a mess that let Cascade catch up, and Makibaō lost by a close video check.

Chūbei was badly hurt and damaged his spine, making it impossible for him to race again.

Japan Derby

Although Chūbei was told he could die if he rode again, he could not give up his passion.

He was given doctor approval only if he stayed in Kansuke’s pocket and didn't take risks.

Feeling the team needed him, Chūbei jumped onto his usual spot during the final straight, cheering on Makibaō.

Makibaō finally caught up with Cascade, and both finished at the same time.

Sadly, this victory cost Chūbei his life. After seeing his partner win, Chūbei peacefully passed away.

Makibaō, Kansuke, Cascade, and everyone else mourned his loss.

Cascade, who was usually tough, was clearly shaken and respected Chūbei even more from this experience.

Aftermath

Makibaō was so shocked by Chūbei’s death that he couldn’t race properly anymore.

He kept seeing Chūbei’s ghost and was afraid to run full speed, worried that he might hurt Chūbei again.

But with help from visions of a brave Chūbei, Makibaō overcame his fears and returned to racing.

After Makibaō finally defeated Cascade, he reported his victory to Chūbei.

In the Anime Version

In the anime, Chūbei does not die after the Derby, but his wounds make him stop racing.

He chooses to support from behind and still joins the training as a helper.

The anime made more changes to be fun for younger viewers, adding explanation parts and light-hearted characters.

Chūbei’s possible fate and his dramatic moments were carefully discussed by the voice actors and staff to make the anime friendly for kids.

Chūbei was treated at the "National Mouse Hospital," which looked like a normal human hospital, but had details for mice like small IV drips.

Even in a world where mice and horses talk, this scene was memorable for readers.

In the anime opening song "Hashire Kōtarō," there is a line about the jockey being thrown off near the end, which seems to match Chūbei’s character and his big moment.