Yuko Minami (南夕子 Minami Yūko) was once one of Ultraman Ace's two human hosts, along with Seiji Hokuto her close friend. The two became hosts for Ultraman Ace after they lost their lives trying to help a group of orphans get away from the first Terrible-Monster of Yapool, Verokron. When they bring their Ultra Rings together the two combined to form the giant of light, Ultraman Ace.
Originally from the moon, her home was destroyed by Lunaticks, one of the oldest Terrible-Monsters. Most of her people were killed but some survived and wandered the galaxy as nomads. Yuko returned to Earth to fight against Yapool, but her comrades in space eventually called on her to their new home. This was around the same time Lunaticks appeared on Earth, eventually revealing her true nature to Seiji, as Ultraman Ace they avenged the lunar civilization. Afterwards she left, donning a white garb, she left her Ultra Ring and her connection to Ace for Seiji, wishing both Ace and Seiji goodbye as she left Earth for the moon to take part in rebuilding the civilization there.
She reappears once more with the Father of Ultra in a Santa sleigh. She comes to cure the people who have been blinded by Snowgiran with her arm. Afterwards she goes back to the moon and says goodbye to Seiji Hokuto.
During Taro's time on Earth, the invading monster Mochiron had come and disturbed the Earth on a day known as "Mochi Day" and refused to leave until he had consumed enough Mochi to satisfy himself. Working alongside Ultraman Taro and Father of Ultra, Yuko grew to giant proportions to help them in making enough Mochi to satisfy Mochiron. Once the monster was full, Yuko and Father of Ultra carried him off into space.
Later on, during Ultraman Mebius' stay on Earth, she would appear to an older Seiji, fighting again as Ace, to help Crew GUYS Japan, against Lunaticks on the moon.
Great Decisive Battle! The Super 8 Ultra Brothers
An alternate reality version of Yuko appears with Seiji as his Earth-born wife. At the end when the Ultra Brothers remember their true selves she is seen helping the injured in the emergency medical station. She and Seiji had one daughter who helped her. At the end of the movie she and Seiji went off into space with the others.
- Height: 160 cm
- Weight: 55 kg
- Age: 19 years
- Date of Birth: July 7, 1953
- Blood Type: O
Ultra Rings: Hokuto and Minami are each given a ring to summon Ultraman Ace. When the rings touch, both hosts combine to form Ultraman Ace. After Minami left back to the moon, Hokuto wore both rings and was able to transform into Ace on his own.
- Powers and Weapons
- Combat Training: Like any defense team member, Yuko is a trained pilot and marksmen.
- Flight: Due to her extra-terrestrial origins, Yuko can fly under her own power, perhaps even interstellar distance.
- Size Change: Yuko can grow to giant proportions in desperate times.
- Telepathy: It is implied during her reunion with Ace and Seiji during the time of Mebius that she had contacted them telepathically.
- Healing Light: Yuko once released a ray of light from her hands, which healed the victims of Snowgiran of their blindness.
- Ultra Ring: Minami and Hokuto can transform into Ultraman Ace by touching the rings together.
- Yuko is the first female to serve as an Ultra's host.
- She is also the first Ultra Host after Shin Hayata to separate from her Ultra.
- Yuko is the first alien Ultra host, though biologically she is descended from humans.
- During her return in the Ace series, Yuko is seen and heard playing the piano to herald her arrival to Seiji. The tune she played was Beethoven's Moonlight Sonata.
- Aside from being the hosts for Ultraman Ace, Seiji and Yuko share another similarity. Both of their surnames have the kanji for geographical directions: Seiji's surname, Hokuto (北斗Kita), and Yuko has South (南 Minami). ) has North (北
- Similar case to Mitsuhiro Ide and Anne Yuri, the role of Yuko Minami was originally given to another actress named Kaori Seki. However, Seki suffered an accident before the series' filming. Thus, Mitsuko Hoshi was chosen to replace her. Seki later appeared as a guest character in one episode.
- Her initial proposed name was "Nanako Minami" (南七子 Minami Nanako).
- Yuko is a big eater, as seen in episode 19, where she ordered an oversized ramen.