Tenchi Masaki. A member of the Masaki Gentlemen's Association. He was a perfectly ordinary high school student attending Okayama Prefectural Kurashiki Nishi High School until he accidentally released a mummified demon (actually Ryoko) sealed in the Masaki Shrine storehouse, leading him into a life of supernatural phenomena and constant trouble with women. Through various events, he learns he is a direct descendant (great-grandson of the current Jurai Emperor) of the Masaki family, one of the four royal houses of the Galactic Union's largest power, the monarchical state of Jurai. He later withdrew from high school for certain reasons and now effectively works as a carrot farmer. He has a serious, honest personality and deep compassion for others. He is extremely popular with women but remains oblivious to it. He can be indecisive and is very shy around romance, often described as a "blockhead" or "dense." Despite the intense affection from the beautiful women around him, his non-committal attitude often leads them to take aggressive, forceful measures. He is the only being capable of manifesting "Lighthawk Wings" on his own without the power of a Royal Tree, and is a master of the materialized "Lighthawk Sword." He was previously limited to three wings at once. He has awakened as a high-dimensional lifeform (trans-dimensional being) surpassing Washu and the other three Goddesses. Since then, he can manifest up to six wings, though his inherent capacity allows for ten or more. As a result, he has stopped aging (he is not immortal, but does not age). Furthermore, his power has caused those around him—Ryoko, Ayeka, Sasami, Noike, Mihoshi, Ryo-Ohki, Washu, and even Seina—to stop aging as well.

Katsuhito Masaki. His name in Jurai is Yosho Masaki Jurai. Tenchi's grandfather and the chief priest of the Masaki Shrine. His true identity is Yosho Masaki Jurai, the Crown Prince born to Azusa Masaki Jurai and Funaho of the planet Jurai. He maintains his youth through the power of his Royal Tree, "Funaho," and his elderly appearance is a disguise. Because his mother, Funaho, was from Earth—a primitive civilization without spaceflight technology at the time—his position was weak, and he was constantly required to be excellent (he trained himself believing his own merit would protect his mother's status). His engagement to Ayeka was arranged by Funaho and Misaki to reinforce his position as successor. While studying at the Galaxy Academy, he met Airi Maguma, who was guiding new students. They fell in love, but she was forced to return to Airai mid-studies for an arranged marriage, though she was pregnant with his child at the time. Heartbroken by the separation from Airi 700 years ago, he was caught in Ryoko's attack while visiting home from the Academy. He pursued Ryoko, who had infiltrated the Royal Palace (Tenju), to Earth and succeeded in sealing her. However, using his ship's damage as an excuse, he faked his disappearance and went into exile. He met Kasumi, his mother Funaho's niece, married her, and settled on Earth. Over a century later, around the time of Kasumi's death, he worried about the future of his children who shared the Masaki name and lived longer than humans, so he contacted a friend at the Galaxy Academy. This led to a reunion with Airi and the discovery of his daughter, Mizuho. This sparked a common-law relationship with Airi, with whom he had Kiyone. Even after establishing contact with them, for unknown reasons, he did not communicate properly with his parents until Ryoko's resurrection, and officially he is still treated as deceased, with his survival being a top secret. Described as a master tactician, he kept in close contact with Seto Kamiki Jurai, another expert in information warfare, allowing him to stay well-informed about galactic affairs despite being on Earth. According to Kajishima, Yosho initially intended to make Tenchi the successor to Jurai in his place, but changed course after realizing Tenchi was "too big for the vessel of Jurai." Currently, those with succession rights are Yosho, Tenchi, and Seina, but Airi speculated that Yosho decided not to force the throne upon the younger generation to avoid stealing their freedom (intending to eventually succeed it himself). He is the master of the first-generation ship "Funaho," named after his biological mother. Being chosen by a first-generation Royal Tree is extremely rare in the long history of the Jurai Royal Family, with only three cases prior to Yosho's father, Emperor Azusa. Funaho is smaller compared to other ships.

Azusa Masaki Jurai. The current Emperor of Jurai. Yosho's father and Tenchi's great-grandfather. Because his mother left the Masaki family to marry into another house, he was born on a planet outside Jurai territory, but was later brought back by Seto to become the head of the Masaki house. During his warrior training before ascending the throne, he was injured fighting Kagato and Ryoko, and met Funaho on Earth while stopping there to recover. In his youth, he was a fine example of a Masaki man: possessing a sharp mind and calm judgment, yet also impulsive, hot-blooded, and freedom-loving (traits that still peek through even now as a father and Emperor). He is the master of the first-generation ship "Kirito." After his first consort Funaho passed away, he took Seto's daughter, Misaki, as his wife.

Nobuyuki Masaki. Father to Tennyo, Tenchi, and Kenshi; an architect. Though he married into the family, he is a descendant of Yosho (Katsuhito) and Kasumi, and his facial features and behavior closely resemble his father-in-law/ancestor. Although he is over 120 years old, his middle-aged appearance as Tenchi's father is a disguise; his true form looks like an Earthling in his 20s. He lost his parents at a young age and was raised by Kiyone Masaki, whom he later married. After her death, he remarried Rea. Unusually for a member of the Masaki household, he has never traveled into space.