Yuzuki Shijō, known as Yuzu, originates from the unseen world known as the Common, a realm formed from gathered human emotions. She and her twin sister, Lime, serve as Guardians tasked with protecting both the Common and the real world from the Sephirot entities threatening planetary stability. Their existence stems from a tragic accident that claimed their lives prior to the series' events. Hospitalized before their deaths, they witnessed Hinako Shirai's ballet performance on television, inspiring them to befriend her. This led them to recruit Hinako as a Reflector—a magical guardian—by granting her a transformation ring.

Physically, Yuzu possesses long blonde hair styled in braided pigtails secured by red ribbons, brown eyes, and stands 147 cm tall. She typically wears the Hoshinomiya Girls' School uniform featuring a blue neck ribbon, blue knee-high socks, and brown dress shoes. Her Reflector form attire shifts to a ballet-inspired design: a white and blue leotard, a short skirt with a front slit, thigh-high boots, and a translucent purple half-mantle. She wields a scepter that splits into dual batons for blunt strikes or magical assaults.

Yuzu exhibits a cheerful, warm, and energetic personality, frequently telling jokes and using puns. She often assigns nicknames to others and maintains a positive outlook, contrasting with Lime's stoicism. This genki demeanor makes her widely liked, though she remains deeply committed to her Guardian duties. Her combat role emphasizes support, leveraging high speed and defense to aid allies while utilizing floral-themed magical attacks.

In *Blue Reflection*, Yuzu and Lime initially deceive Hinako by promising a wish in exchange for defeating Sephirot—a tactic to secure her cooperation. The truth reveals their inability to grant such wishes, and their victory necessitates a timeline reset erasing memories of them. Their motivation stemmed from admiration for Hinako's ballet, forged during their final days. The sisters later confront Daath, a deity seeking to assimilate humanity to combat the Sephirot. After Daath's defeat, Yuzu and Lime return to the afterlife, though Hinako's wish preserves her memories.

In *Blue Reflection Ray*, Yuzu and Lime reappear as spiritual advisors, guiding Reflectors like Hirahara Hiori against antagonists such as Mizusaki Shino. They act as the Common's last line of defense when other Reflectors are incapacitated, emphasizing their enduring Guardian role.

During *Blue Reflection Tie/Second Light*, the twins create Oasis—a sanctuary island school—to protect Reflectors from the Ash Phenomenon, a crisis causing critical illness. Complications in sustaining Oasis cause Yuzu to lose her emotions, while Lime falls comatose after sacrificing her power. Both are restored through the efforts of Hoshizaki Ao and other Reflectors. The sisters later assist in confronting the World System, the entity behind the Ash crisis.

Yuzu appears briefly in *Blue Reflection Sun*, though specific narrative details remain undisclosed.