Koushirou is Roronoa Zoro’s former swordsmanship teacher and father of the late Kuina. His father, Shimotsuki Kozaburo, was from Wano Country and founded Shimotsuki.
Koushirou is an older man with dark, long hair, which he always wears tied in a ponytail. On his nose sits a pair of glasses with round lenses. Most of the time he wears a grey suit, which strongly reminds of a judo or karate suit. He wears this suit in combination with a Hatchan. Since he spends most of his time in his dojo, he also doesn’t wear shoes. He can be seen most of the time with a broad smile and with closed eyes.
Koushirou is a relatively strict teacher, but he believes in his students and wishes only the best for them as long as they stick to the art of swordplay. However, he believes that women, no matter how hard they train, can never be superior to men, as they simply have worse anatomy. He took the death of his daughter in stride. He also places great trust in Zoro, as he entrusted him with the sword Wado-Ichi-Monji after his daughter’s death.
Skills and strength
As a sword master, he must be very skilled in the use of the sword. As a teacher, he could produce two outstanding swordsmen like Zoro and Kuina. In addition, he has mastered the high skill of “cutting without splitting”.
Koushirou runs a dojo, where he also taught Zoro and his own daughter. His daughter Kuina was the best swordswoman in the dojo; even Zoro was always defeated by her and could not record a single victory against her.
Shortly after Sabo’s incident with Saint Jalmack, Koushirou allowed some revolutionaries to help themselves to his supplies and replenish their own.
Koushirou spoke to a member of his dojo one day that Zoro would soon become stronger than Kuina, as she would one day be unable to keep up with the boys due to her anatomy as a woman. His daughter overheard this conversation secretly and subsequently told Zoro. Thus the two swore to each other that one of them would become the best swordsman in the world.
The next day Koushirou’s daughter died in an accident. When Zoro told about his promise with Kuina and asked for the Wado-Ichi-Monji, Koushirou gave it to him willingly, because he put his trust in Zoro.
As the wanted posters of the Straw Hat Pirates went around the world, Koushirou noted that it was fine for Zoro to be a pirate as long as he didn’t stray from the path of the sword.
When the reappearance of the Straw Hat Pirates on the Sabaody Archipelago was reported, Koushirou smilingly brought a copy of the newspaper to Kuina’s grave.
After the events at Dress Rosa, many of Koushirou’s younger students were seen to be emulating Zoro. They put a band-aid over their left eye and trained with three swords at once. Koushirou’s enthusiasm was held in check.
- Koushirou’s favorite dish is watermelon.