Depending on whether you watch the OVAs or the TV series, Ryoko is either a 5,000-year-old "demon" and wanted criminal resurrected by Tenchi, or a space pirate who crashed on Earth when being chased by the Galaxy Police. Either way, Ryoko is a powerful being with the capability of flight, teleportation and use of energy weapons, who now lives at Tenchi's house. Although much of the time she can be loud, brash and unscrupulous, she is a deeply sensitive character with a real affection for Tenchi.

Ayeka is, outwardly, the very opposite of Ryoko. As the crown princess of Jurai, she carries herself with dignity and a genteel manner. However, Ayeka does occasionally show a darker, more severe side, and under her placid exterior lies a core of steel-hard will. Forced to live on Earth when, in pursuit of Ryoko, her spaceship is destroyed, she too has grown fond of Tenchi, and is forever fighting with Ryoko over his affections.

Many believe that Mihoshi is simply the 'comedy relief' to the Tenchi series. True, she is clumsy, accident-prone, easily distracted and often an embarrassment to the Galaxy Police. However, she is cheerful, hardworking, brave in a crisis and can be a perfectly competent police officer at times, particularly thanks to her almost superhuman good fortune. She carries a huge array of fascinating GP-issue gadgets, from her all-purpose control-cube to her wristband radar.

Kiyone is a detective in the Galaxy Police, and Mihoshi's long-suffering partner. In service of the Galaxy Police, her performance is exemplary, as she is level-headed, quick-witted and dedicated to her job. Her personality is quite the opposite of Mihoshi's, and this makes her a tough character to discern - she rarely expresses her emotions outwardly (beyond regular exasperation and anger directed towards Mihoshi).