Isao Sato is a main character and protagonist in Red Steel. He is the father of Miyu Sato. He's also the leader of a Yakuza clan called Sato Gumi. But it is an honorable clan that deals in legal companies rather than crime.
Act 1: Sato's Legacy
But before the meeting actually takes place, a gang of thugs disguised as hotel staff attack them. Scott was knocked unconscious and Sato had his men escort Miyu to his personal suite. Sato soon found himself injured on the roof of the hotel, but Scott surprisingly came to his rescue. He insists they head down to the suite to meet up with Miyu.
Along the way, they find a sword. Sato gives Scott a crash-course lesson in sword fighting. Because of all the sword-wielding enemies they come across, Sato figures they are being attacked by members of the Yakuza, a Japanese crime syndicate.
Upon reaching the suite, they are greeted by Sato's friend Ryuichi who was keeping Miyu safe. They fight their way to the lower levels of the garage under the Hotel to make their escape. But when they get there, Ryuichi turns on them and attempts to kidnap Sato and Miyu. Scott manages to stop one car and rescue Sato, but Ryuichi is able to escape with Miyu.
So Scott heads out looking for Angel while Sato stays with Tony Tanaka to recover from his wounds.
When Scott finally returns to Tony's store, he explains that Ryuichi got away with Miyu and demanded the Katana Giri. Sato then tells Tony to give Scott the sword, which has been hidden in the store's basement. After Tony gives a brief lesson to Scott in swordplay using Sato's style, Sato's dying wish was to have Scott rescue his daughter, Miyu.
After Sato dies, Scott flies to Japan.