Don't compare yourself to other people. The opponent you fight is always yourself. What's important is becoming stronger than you were yesterday. If you continue that for ten or 20 years, you'll be magnificent. And then you will help other people.
Keizo is a middle-aged man with a muscular body and unshaven stubble. He kept a shoulder length black hair which was tied and his eyebrows appears to be quite bushy.
Keizo is a kind and cheerful person, doing his best to protect the others with his abilities, and he was optimist and empathic enough to assign Hakuji, a former convict, to take care of his daughter, teaching him his Soryu martial arts and ultimately welcoming him into his family by allowing him to marry Koyuki and be the next head of his dojo. His memory and instructions impacted Hakuji enough even after his transformation as a demon and the loss of his memories, especially after meeting Tanjiro Kamado who shared his same beliefs and benevolence.
Keizo gets a dojo after saving a man from bandits. He was married, and had a daughter, Koyuki, who was ill. His wife drowns herself because she didnt want to see her daughter die, after that he took care of the child alone but didn't believe she would live long. He was travelling and found Hakuji and took him to his dojo after easily defeating him in a fight, and requested him to take care of his daughter, which Hakuji did.
Keizo was angered by the fact that the heir of the dojo next door forced his daughter outside and abandoned her when she was in bad shape. Thus, he arranged to have a match between the Soryu dojo and the dojo next door. However, Keizo went easy on them.
When his daughter becomes 16 he asks Hakuji to take over the dojo and marry his daughter. He was then poisoned by the people from the neighboring dojos dumping poison in the well where he and his daughter drank from while Hakuji was out visiting his father's grave.
After drinking the poison, Keizo held Koyuki and ran to the doctor's home as he was spitting blood. Koyuki was already dead, but it took several hours for Keizo to die. He suffered for a long time.
Master Hand-to-Hand Combatant:
- Soryu Style (
素 流 式Soryū Shiki?): A bare-fist martial arts fighting style that Keizo either invented himself or was taught by his own master. He was able to overpower Hakuji when he first met him despite the ladder being able to defeat seven grown adult men.
- The reason why his dojo never had any students was because they all went to the neighboring dojos, which were his dojos rivals because they wanted his land.
- (To Akaza) "Whatever you do, everyone is a baby at first. You get help from others and gradually learn. Don't compare yourself to other people. The opponent you fight is always yourself. What's important is becoming stronger than you were yesterday. If you continue that for ten or 20 years, you'll be magnificent. And then you will help other people."
- (To Akaza) "Our indomitable spirit in whatever hardship we face, it never breaks. We are not samurai. We do not carry a katana. But we carry swords in our hearts."
- (To Hakuji) "Yes, but I beat up and defeated that criminal earlier, so it's all right now!"
- (To Akaza) "Time for you to be reborn!"