Sasami
This junior princess of Jurai is cast by Mihoshi in her story as a young Galaxy Police apprentice detective (and tea maker) with a secret. Sasami moves on to a starring role in the Pretty Sammy specials as the middle schooler Sasami Kawai who remains cheerful despite having to put up with a karaoke-crazy mom, an indecisive older brother, and a squabbling pair of rivals for his affections. As if that wasn't enough, she's chosen by Tsunami to fight for the forces of good as the magical girl Pretty Sammy (with help from her advisor and pet, Ryo-ohki)!
Mihoshi
A bumbling and bubble-headed Galaxy Police Detective that makes her partner Kiyone miserable in the Mihoshi Special. In the Pretty Sammy specials, Mihoshi is a carefree college student that drives her roommate Kiyone crazy. She works along with Kiyone at the CD shop owned by Sasami's mother Chihiro.
Tenchi
A kindhearted fellow who (reluctantly) finds himself the center of attention of a group of lovely and competitive ladies. Tenchi appears in the Mihoshi Special as a special investigator from Galaxy Police HQ who is working on the case of the stolen Ultra Energy Matter when he is kidnapped by the perpetrator, space pirate Ryoko. In the Pretty Sammy specials, he appears as Tenchi Kawai, Sasami's indecisive older brother who ends up as the romantic prize (and occasional punching bag) of the rivalry between rich girl Ayeka and tough gal Ryoko.
Ryoko
The tough and sexy space pirate with a gentle heart ends up in Mihoshi's story playing...a space pirate. Only this time she has a mysterious connection to the mad scientist Dr. Washu, a low-rent hideout, and is even more assertive in her quest for Tenchi's affection. Meanwhile in the Pretty Sammy world, Ryoko plays a tough yet tender classmate of Tenchi who constantly fights with Ayeka to determine which of them will have him all to themselves.
Ayeka
The proud princess of Jurai finds herself cast in Mihoshi's story as the wealthy heiress to the Jurai Plutocrats, who also happens to be the slightly jealous self-appointed fiancé of Investigator Tenchi. In the Pretty Sammy specials, Ayeka plays a slightly wacky rich girl and student council head who uses her expert martial arts skills to battle Ryoko for the love of Tenchi.
Washu
A genius scientist hiding behind a childish facade who is intent on ‘studying’ Tenchi, Washu is cast in a more sinister role in Mihoshi's story as the evil mad scientist Dr. Washu, who is bent on destroying the galaxy. In the Pretty Sammy specials, Washu plays a slightly manipulative child prodigy who moves to Sasami's town in pursuit of her research on magical energy. She also happens to teach science at the local school despite her tender age.
Kiyone
Mihoshi's long suffering Galaxy Police Detective partner, Kiyone sees her career (and life!) threatened time and again by the bumbling blonde's slip-ups. Kiyone appears in the Pretty Sammy specials as Mihoshi's exasperated roommate who failed her college entrance exams and now works part time at the CD shop while studying for the next round of entrance exams.
Ryo-ohki
A cute carrot-loving furball that transforms into a spacecraft, Ryo-ohki appears as Sasami's talking sidekick in both Mihoshi's story and the Pretty Sammy specials. However in the Pretty Sammy specials Ryo-ohki was sent by first queen candidate Tsunami to help Pretty Sammy become an effective magical girl, and may even have a different form while in the magical kingdom of Juraihelm.
Misao Amano
Sasami's subdued classmate and friend, Misao is a shy and lonely girl from a troubled family. She is being used by Ramia to defeat Pretty Sammy by transforming Misao into the flamboyant Magical Girl Pixy Misa. However, Misao retains no memory of her escapades.
Tsunami
Ignoring her role in the Tenchi Muyo continuity, in the Pretty Sammy specials Tsunami becomes the first choice candidate for queen of the magical kingdom of Juraihelm. She is charged with proving herself to be worthy of the role by enlisting Pretty Sammy in making the world a better place.
Chihiro Kawai
A failed pop singer who now owns a CD store, Chihiro is Sasami's and Tenchi's mother. She seems much more adept at singing karaoke than housework, so Sasami ends up being the one to keep the household running smoothly.
Makoto Mizushina
A mysterious boy who works at a hotel by the beach that Sasami and her friends travel to on their vacation. He somehow knows exactly what Sasami is thinking.
Ayeka's Henchwomen
These girls are devoted to assisting their classmate Ayeka in her quest to win the heart of Tenchi.