He is a master of a martial arts technique called Drunken Fist, a technique which involves making yourself look vulnerable so the enemy underestimate you. He uses this technique to fight off several Samurai who try to take Jack away at the beginning of the book. According to him, he learnt the skill from a warrior named Han Zhongli, after witnessing him take out 21 of his adversaries at one go.
Ronin constantly drinks sake (a strong alcholic drink made from fermented rice) and becomes grumpy and irritable if his supply drops. It may seem that he loves it, but there is a tragic reason behind his drinking habit. Some time ago, a spy disguised as a monk managed to assassinate his father, and Ronin was unable to stop the killing. As a result, he was consumed by guilt and despair, and took to drinking to forget his past. He also developed a hatred for monks, and it was this hatred that drove him to take Botan's job of trapping and interrogating a monk (Jack).
Agreeing to the plan, Ronin successfully drugged Jack, but afterwards, as the gang rob Jack of his possessions, he is stunned to find that he is a foreigner. Botan's gang tries to kill him, but Ronin tries to stop them, saying that he cannot let them murder an innocent boy, but soon collapses as Botan had drugged his sake too. Botan drops Jack's rutter on his body before proceeding to beat Jack up.
He would awake, not remembering anything at all. The Riddling Monk then appeared, and challenged him to a riddle. In no fit state to give the correct answer, Ronin gets it wrong and the Monk then takes the rutter away from him. He then makes his way to a roadside inn where coincidentally, a badly injured Jack is nursing his wounds.
As the doshin try to arrest Jack, Ronin stops them by using his Drunken Fist skills. He then beckons Jack along with him to avoid his pursuers.
When Hana appears on the scene he is at first distrusting of her as she is a thief, but later warms to her and starts to develop a strong relationship with her. He also becomes good friends with Jack, assisting him on his quest to recover his belongings.
Ronin is a master of the fighting style the Drunken Fist, and his skill with the sword is undeniable.
- Jack Fletcher - At first he is grumpy and irritable towards Jack but they soon start to warm to each other and Ronin teaches Jack the principles of Drunken Fist fighting style which he picks up quickly.
- Hana - at first he is cold towards her but they both start to become close over the course of the book until they are very close and develop a realtionship that is almost like that of a father and daughter. He teaches her the Drunken Fist.