Yuzu Hiragi or Yuzu Hiiragi (柊ひいらぎ 柚ゆ子ず Hīragi Yuzu), known as (Zuzu Boyle in the English dub) is Yūya Sakaki's childhood friend in the Yu-Gi-Oh! ARC-V anime. She gives powerful pep talks. Her father owns You Show Duel School, the Duel school that she and Yūya attend. She is the Standard Dimension counterpart of Lulu (from the Xyz Dimension), Rin (from the Synchro Dimension), and Celina (from the Fusion Dimension).
She is voiced by Yuna Inamura in the Japanese version and Emily Jenness, who also voices Dawn in Pokémon, in the English version.
Yuzu has blue eyes and dark pink hair, which she wears tied up in pigtails, clipped down by blue, spherical hair clips. Her hair also features two lighter pink bangs that fall to the side of her face. Yuzu's outfit consists of a sleeveless light-blue and white shirt with a musical note on the right collar, along with a red tie, which she wears with a dark red skirt and dark stockings. Her skirt is lengthened in the dub to cover the bare skin showing on her legs. She notably is not shown wearing the school jacket from Maiami Second Junior High School that other female students wear. She also wears a bracelet with strange abilities. These powers seem to be connected to Yūya and his counterparts, activating whenever Yuzu, Yūya and any of his counterparts are in close proximity. She later switches clothes with Serena, but she retains her bracelet, her spherical hair clips and her Duel Disk. Later, she starts wearing some of Rin's clothes while staying at Yūgo's orphanage in the Synchro Dimension. Yuzu wears one of Rin's Riding Dueling outfits for the Friendship Cup; a predominantly white one-piece short-sleeved jacket-miniskirt combination with light pink shoulder pads and hot pink markings, in addition to back pockets; long white gloves with light pink elbow pads that extend over her elbows, hot pink pants, and white knee-length form-fitting boots with light pink kneepads. While in the Underground Labor Facility, Yuzu wore one of the facility's uniforms: a dark red full body suit with a hood and brown shoes without socks. After arriving at the Fusion Dimension's You Show Duel School, Yuzu receives a change of clothes from Asuka Tenjōin; a sleeveless white shirt with a pink pad over her chest and shoulders, a pink skirt and a white belt. She also wears white boots.
Yuzu is shown to be very sweet and kind but gets upset easily, often resulting in her actions causing huge consequences. An example of this would be when she smashed her fists down on the Solid Vision technology computer at You Show Duel School out of annoyance of how Yūya was Dueling, which ended up destroying the machine. Zuzu also has a tendency of whacking a paper fan on other people's heads, primarily Yūya and Shūzō, whenever they do something foolish. She is also shown to be quite argumentative, wanting to argue with a spectator who insulted Yūya and his father before his Duel with Strong Ishijima, showing that she can be just as defensive and caring of Yūya and his belief in his father.
Her perception and judgement begin to falter after her successive encounters with Yūto, due to Yūto's resemblance with Yūya, and her lack of knowledge of the subject frustrates her. These worries are put at ease after the encouragement from Yūto and Yūya, returning her resolve to become stronger so she can protect You Show Duel School and her friends.
She harbors feelings for Yūya, initially shown when she was blushing after Sora mistook her as Yūya's girlfriend and whenever Mieru Hōchun makes advances towards Yūya. The strongest examples so far included when she started to cry when she was worried that Yūya would never awake while he was unconscious for a few days after his encounter with Yūto and Yūgo, and upon being separated from Yūya in the Synchro Dimension.
The character's name, "Yuzu" (柚ゆ子ず), means Pomelo, and her surname, "Hīragi" (柊ひいらぎ), means Osmanthus heterophyllus. Both names are related to plants and fruits. However, her Deck nor anything about her is based on or is about plants and fruits.
Zuzu is a variation of her Japanese name, while her surname may be based on singer Susan Boyle, as a reference to the Deck she uses.
Yuzu is quite athletic and acrobatic. Since her debut she was able to smash the Solid Vision Technology to the point where it malfunction in one punch. When she later refuses to go with Yūri she preforms several backflips and land with ease. She is also shown to be strong enough to shove Yūgo several feet backwards after lying prone, which nearly injured him and damaged his D-Wheel.