Yoko is a fairly tall and youthful-looking woman of slender built with green eyes and light skin. She has long blond hair the front bangs being golden in color. Her hair is tied in a ponytail and sections out as spikes. Her bangs part to the right side and frame her face. She is commonly seen wearing and aqua-colored long-sleeve shirt and blue jeans with brown low shoes. She also accessories with silver big-loop earrings, two golden bands on her left wrist, and a small golden necklace hanging under her neck.
Yoko is a kind-hearted woman, and is shown to care a lot for Yuya. She understands his true feelings, as seen when she told Skip Boyle that Yuya spent the last several years acting like a clown to cope with Yusho Sakaki's disappearance.
However, Yoko is easily charmed by anything she deems cute, such as Sora Perse when he stayed at the Sakaki residence, up to the point she gave Yuya's breakfast to him,, as well as several other young boys such as Reed Pepper and Dennis McField. In these situations, she will not hesitate to support them more frequently than her own son. Yoko's love for cute things also has caused her to adopt several cats and dogs, including En, Core, Kilo and Watt.
In her youth, Yoko was the leader of a female biker gang called the "Sirens" (the "Maiami Queens" in the Japanese version), as "Loco Yoko" and the "Queen of the Sirens" ("Shooting Star Yoko" in the Japanese version). At one point, one of her teammates was held hostage by a member of a rival gang. Yusho Sakaki stepped in and saved her. Yoko was touched by Yusho's ability to end fights peacefully without violence and developed feelings for Yusho. The two of them eventually got married and had a son (adopted actually), Yuya Sakaki, together. Through Yusho, Yoko also befriended Skip Boyle.
When Yusho did not show up for his Duel against The Sledgehammer, Yuya ran to the bottom of the stands and challenged Sledgehammer to a Duel in his father's stead. Yoko pulled Yuya away as he continued to protest.
Pre-Arc League Championship
Yoko showed up during Yuya's Duel against The Sledgehammer. She told Skip, Zuzu and Gong about Yuya's behavior: he had acted like a clown to cope with Yusho's disappearance and reinvented himself while Dueling. She watched the rest of the Duel with the three, and was proud of her son when he won.
Yoko eventually invited Sora to stay at the Sakaki residence, to Yuya's annoyance. She prepared breakfast for the two boys, but she was taken in by Sora's cuteness after he called her Yuya's older sister rather than his mother, causing her to give Yuya's food to him.
Yoko made an appearance during Yuya's Duel with Reed Pepper. Having failed to make one of his recipes due to its complexity, Yoko converted it into a pancake sandwich, which infuriated Reed. She gave her creation to Yuya, who struggled with the Duel as he was too hungry to continue, and smiled as he was re-energized and won the Duel.
Arc League Championship
Yuya had failed to board You Show Duel School's bus on the inauguration of the Arc League Championship. On Zuzu's request, Yoko tracked Yuya down at the bridge overlooking the Paradise Stadium from a distance, and told Yuya to meet with the rest of the team there. Yoko then met up with Skip to cheer on their students as they entered to greet the crowd during the opening ceremony.  Yoko watched Zuzu's rematch with Julia Krystal, Yuya's rematch with Sylvio Sawatari, and Sora's duel against Shay Obsidian which turned violent.
Yoko took Yuya in after he fell unconscious that night; as he rested for two days, Zuzu started to cry over his condition as well as Sora's disappearance. Yoko believed her son would pull through just like he did against The Sledgehammer. She and Zuzu also convinced Aura Sentia, who was also worried for Yuya, to return to the stadium for her match at the Arc League Championship.  Yoko returned to Paradise Stadium to watch the Junior Division Battle Royal, voicing her support for Reed.  She also cheered for Dennis McField during his duel against Zuzu, much to Skip's chagrin. 
After the announcement that the Arc League Championship would be called off, Yoko and Skip met with Yuya, Gong, Aura, Allie, Frederick and Tate. After Gong departed, Yoko took Yuya to an abandoned arcade and beckoned the rest to follow. There, she revealed her past life to Yuya, and challenged him to a duel while chasing him across the arcade on her old motorcycle.  During the duel, Yoko reminded her son that his desire to save Zuzu was shared by everyone at You Show Duel School; this made Yuya recall his father's words. After losing the duel, Yoko entrusted "Smile World" to Yuya, and was confident that Yuya would see his mission through: to save Zuzu, bring her home and end the fighting.  Yoko bid Yuya farewell before he left with the Lancers for the Synchro Dimension.
After Z-ARC's defeat and the Standard Dimension being reborn into the "Pendulum Dimension", Yoko had lost her memories of Zuzu and the events involving people from other dimensions. She prepared breakfast for Yuya and wondered why he was in a hurry when it was Sunday. She told yelled at him for making a mess when he was talking with food in mouth. She was present during the Battle Royal with Allie, Frederick, and Tate. When Moon Shadow urged everybody to remember the Arc League Championship, Yoko began to recall the events especially Reed being part of it. After Yuya realized that he was Z-ARC, and started having doubts over whether he could save Zuzu, Yoko reminded her son of what he promised to do, the day before he set out with the Lancers, and pointed out that he hasn't accomplished any of what he had promised. 
Yoko uses a "Road Raven" Deck.
|4 Unknown Duelists||52||Win (flashback)|
|Unknown Duelist||52||No result (flashback)|
- Yu-Gi-Oh! ARC-V episode 52: ""
- Saskia Maarleveld's site
- Yu-Gi-Oh! ARC-V episode 1: ""
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- Yu-Gi-Oh! ARC-V episode 17: ""
- Yu-Gi-Oh! ARC-V episode 44: ""
- Yu-Gi-Oh! ARC-V episode 16: ""
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- Yu-Gi-Oh! ARC-V episode 25: ""
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- Yu-Gi-Oh! ARC-V episode 141: ""
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- Yu-Gi-Oh! ARC-V episode 146: ""