In the OVA, Katsuhito, also known as Yōshō Masaki Jurai (柾木 遙照 樹雷 Masaki Yōshō Jurai?), fled Jurai over 700 years ago to "retire" on Earth. He was once the greatest swordsman on Jurai. Currently Katsuhito is a Shinto priest who is not only training Tenchi to be a Shinto priest but also training him in Jurai swordsmanship. Yōshō had a marriage arranged with half-sister Ayeka, but left. At the time, not all Juraians liked the idea of mixed blood heritages (he is part human, on his mother's side) and he used Ryōko's attack as an excuse to slip away to Earth. In the OVA, he expected that Ayeka was trying to track him down and arranged for Tenchi to fight Ryōko so that his grandson would go in his place to Jurai. Although he had dropped contact with his parents, he was still in touch with Seto (through whom he was able to send Tennyo and Kiriko, among others, into space via the Galaxy Police) although her collusion in his plans is not known. While he appears to be of advanced age, his gray hair and lined face are merely an illusion hiding his true form, which he shows to only a select few (such as his mother). Although not noted or addressed, Yosho, can control one Light Hawk Wing, generated by his royal tree Funaho, as seen in the battle with Kagato and the possessed Ryoko in OVA1 Episode 5.
Yōshō's tree is called Funaho, after his mother. It is a rare first-generation tree spawned directly from Tsunami-no-fume and thus one of the most powerful Jurian tree ships (not including its 0th generation 'mother' Tsunami-no-fume and on par with Azusa's Kirito which is also 1st Generation). It is currently rooted on Earth and so at present cannot take ship form. However, the tree has not lost its power. This was because, during his battle with Ryōko, Yōshō had stolen the three gems originally bonded by Washu and bonded them to the pommel of Tenchi-ken (which was created from the wood of the Tsunami tree). As a result, the gems had supplied power to the tree for over 700 years.
He is in a common law marriage with Airi and has two children from that union called Minaho and Kiyone. He has married one other woman in the past after crashing to Earth (named Kasumi, his cousin and Funaho's niece), and his descendents along that line include Nobuyuki, and Kiriko.
In the Tenchi Universe continuity, Katsuhito is still known as Yōshō and is related to Jurai's royal family and is the greatest swordsman who has ever lived, but is not a close relative to Ayeka or Sasami. While Ayeka and Sasami are from a distant branch family, Yōshō and Tenchi are from the main line. This makes Tenchi the direct heir to the throne of Jurai.
In the movie Tenchi Forever! (Tenchi in Love 2), it was revealed that, after he defeated Kagato for the first time, he left Jurai along with his lover, Haruna, but tragically, she died upon arriving to Earth. After he arrived, he fell in love with a girl named Itsuki Masaki, who would become Achika Masaki's mother.
Unlike the OVA continuity, where Katsuhito had retained his youthful appearance throughout his seven centuries on earth and simply chooses to appear as an elderly man, Yōshō of the "Tenchi Universe" continuity truly is as elderly as he appears.
Tenchi in Tokyo
In Tenchi in Tokyo, Katsuhito is not part of any line to Jurai's Royal Family. He is just the wise guardian of the Masaki Shrine. He also doesn't display any kind of special powers in the series. Near the finale, when Washu needed to go to Tenchi to warn him about Yugi, Katsuhito went with her. It is there that Katsuhito revealed to Tenchi that the Masaki family are Earth's protectors that secretly battle against any enemy that is a threat to the Earth and the gems that Tenchi received from his late mother are in fact the power that had been granted to them by the gods of the Earth that repels all evil.
Later, after Yugi began to freeze time and after Tenchi went to fight her, Katsuhito explained to Washu that Tenchi won't kill Yugi as he had preferred to be a kindhearted person which is why Washu and the other women from space are allowed to live on Earth in the Masaki Shrine. Katsuhito explained that through this method it enables for Tenchi to be true to himself and be able to fulfill his Planet Guardian duties. This proved to be true when Tenchi chose to spare Yugi.
In Magical Project S (Pretty Samy TV), Katsuhito and Yōshō appear as Genjūrō Hagakure (葉隠 源十郎 Hagakure Genjūrō?) and Binpachi Hagakure (葉隠 敏八 Hagakure Binpachi?), respectively, in episode 10. Genjūrō Hagakure is the leader of the ninja village theme park and is working to prevent Nobuyuki Onijigoku from turning it to a wild west theme park but had become bedridden. Binpachi is Genjūrō's foolish grandson who had chosen to go over Onijigoku's side as he felt that cowboys were cooler than ninja. At the end, Binpachi chose to go back to his family's side after his grandfather protected him from getting shot by Gunman Girl, and Binpachi responded by distracting Gunman Girl with his Ninja skills until Pretty Sammy destroyed her. Genjūrō then was able to convince a depressed Onijigoku that they could convert the theme park into a mixture of the wild west and ninjas. But to help teach Onijigoku a lesson for what he had tried to do, Genjūrō had him and his assistant bound to the entrance of the wild west park as punishment.