|Home world:||Earth (Nebula M78 Universe)|
|First appearance:||Ultraman Ace Episode 24 "Look! A Giant Transformation in the Middle of the Night" (1972)|
|Affiliation:||Mazaron Man (Master)|
- Height: 160 cm
- Weight: 50 kg
- Origin: Yoshiko's mutation
Yapool targeted Kenta's pregnant mother, Yoshiko and pretended himself to be Kenta's faraway father to mail him a red gemstone as a gift (with a bit of Yapool's curse). Yapool (in disguise of an old man) manifested Mazaron Man out of his hatred towards Ace and summoned a red rain via the red gemstone in the said boy's possession, causing his mother to slowly transform into Yojo. As Kenta chased her, Yojo went inside Mt. Fuji, Mazaron Man's hideout and performed a ritual to give birth to Mazarius. Mazarius was born and began to terrorize the area. All of TAC's attacks were proven futile due to the monster being not entirely exist. When a TAC member about to shoot Yojo, Kenta, her son defended her instead. Feeling angered for her mother turned evil, he took a stone that he brought along which was the source for all of this trouble and threw it to her, reverting Yojo to normal and thus, deleted Mazarius from existence.
- Like Alien Baltan, Yojo uses a recycled Matango sound effect for her laugh.
- Yojo's appearance was based on female ghosts/spirits from various Japanese folktales and urban legends.
Powers and Weapons
- Mazarius birth: Through a ritual, Yojo can gave birth to Mazarius. The monster's existence was supported by her maternal energy. If Yojo is reverted back to a human, Mazarius will vanish.
- Dream Invasion: Yojo can enter into dreams and haunt the victim by chasing them. Used on Kenta to stop him from interfering with her plans.
- Snake: Though not actually a weapon, Yojo was seen carrying a snake, even in Kenta's dream.
The red gemstone which resulted her mutation in the first place can revert her back into a regular woman if it is thrown at her.
|Ultraman Ace Kaiju & Seijin|
|Verokron | Yapool | Chameleking | Vakishim | Garan | Aribunta | Giron Man | Brocken | Alien Metron.Jr | Doragory | Muruchi II | Gammas | Zaigon | Alien Antira | Unitang | Sabotendar | Barabas | Ace Killer | King Crab | Cattle God | Cowra | She-Devil | Hotarunga | Black Pigeon | Android Couple | King Kappa | Zemistlar | Aprasar | Aprasar Fairy | Space Mask | Black Satan | Giant Yapool | Mazaron Man | Yojo | Mazarius | Alien Orion | Sphinx | Alien Hipporito | Lunaticks | Undergroundmon | Gitagitanga | Red Jack | Baktari | Coakes | Bad Baalon | Kaiteigagan | Dreamgillas | Soundgillar | Machless | Snowgiran | Namahage | Alien Fire | Firemons | Alien Steal | Kaimanda | Shishigoran | Iceron | Woo II | Fubigirara | Onidevil | Gasegon | Daidarahoshi | Hanzagiran | Verokron II | Yapool Woman | Univerlages | Aquarius | Alien Revole | Signalion | Geegon | Alien Simon | Jumbo King|