In his childhood, Zha Cai was an orphan distrustful of adults, and he and his friends secretly studied Chojin Kung Fu under pupil Victory Ramenman. However, Chen Zongming discovered the unauthorized training and Ramenman ended it out of fear of being expelled (at the time, he was still training to avenge his parents). Banboro and his friends felt betrayed. He has made a name for himself as Banboro across China as a ruthless killer. He possesses muscles of steel and is impervious to most attacks. Several years later he stole the contents of the Touryuu Gokui Sho. With the exception of Banboro, they gain the abilites of the Gokui Sho and use the Choujin 102 Gei to commit evil deeds. Banboro tries to calm them down but goes mad himself after he accidentally kills a child in the confusion. Eventually Ramenman regains the contents of the Gokui Sho and fights Banboro, but both his Shintotsu Kuigisasa Kyaku and the Meidatsu Houkai Ken are ineffective. He is finally defeated and killed when Ramenman learns his one weak spot and uses the Meidatsu Shiyou Ken.
In the manga he never appears again, but in the anime it is revealed that he is the older brother of Takenoko, and for that reason Ramenman spares his life. He then joins up with Gundam and Hogan as one of Ramenman's comrades.