Because he is an orphan, he found himself in many orphanages and facilities. However, he quickly grew tired of the boring life and frequently escaped, eventually finding his way to the Doya Town, the story takes place in.
Joe Yabuki was an orphan. In his youth, he always moved from orphanage to orphanage. He was bullied and treated as an outcast. One day, he escapes and lives on his own. Joe wanders into namidabashi and then encounters the Doya kids. They attack him but he wards them off. He continues walking and then sees a group of thugs hassle Sachi because she stole some oden. He intervenes and fights them. Danpei tange, a retired boxing coach sees him. He then notices joe has an amazing punch. Danpei continually asks joe to train him and joe eventually obliges. At first, Joe is training really well. However, he is sent to a juvenile detention centre for fraud, after framing Yoko Shiraki out of one million yen. There he meets Kanchi Nishi and they brawl, with Joe being the winner.
Joe is rude and quick to fight, but he can also be very frivolous at times. Because of his rough upbringing he is a delinquent who likes solitude, but he later grows to appreciate his new friends and rivals. He is not very good at understanding women, and essentially only treats them nice out of obligation. As a result of Rikiishi's death he temporarily suffered and failed to hit people in the temple, but he later overcomes this.
He is a bantamweight and his specialties include the cross counter and the No Guard stance. He has extraordinary punching strength, fortitude, and fighting spirit, often standing up after taking killer blows and has been known to counter cross-counters (a double-cross), possessing a raw, natural talent for the sport. He has even countered double crosses with a triple-cross, implying he has high-level technical abilities. Following his fight with Rikiishi, he begins to better develop his guarding.
- He likes waffles.
- When the series first came out, it inspired the Japanese audience of the the time heavily. So much so a group of Japanese communists hijacked a plane.