Rika Orimoto, a young girl from Sendai City, Miyagi Prefecture, experienced tragedy early. After her mother's death when Rika was five, she and her father disappeared a year later during a mountain climb before elementary school. Rescuers found Rika alone near the summit a week later; her father remained missing, his death unconfirmed. Hospitalized, she met Yuta Okkotsu, recovering from pneumonia. Rika was then taken in by her paternal grandmother, who held a strong belief that Rika had killed her parents. Befriending Yuta and his younger sister, she attended the same elementary school. At eleven, Rika stole her mother's wedding ring from her grandmother's dresser, gifting it to Yuta for his birthday and promising to marry him when they grew up. Some time later, Rika died in a car accident, her head crushed. Witnessing her death, Yuta unintentionally cursed her while begging her not to die, transforming her into a special grade vengeful cursed spirit. This curse lasted six years, causing Rika to act aggressively towards Yuta's family and others, forcing him to distance himself. Her violence drew the attention of jujutsu society, prompting Satoru Gojo to intervene. As a cursed spirit, Rika manifested as a monstrous entity: a muscular upper body, long arms, and a tail-like shadow. A single cycloptic eye, typically concealed behind a brain-like shell, peered out; tendrils extended from her head, and she possessed long, untrimmed fingernails. Her personality became intensely aggressive and protective, driven solely by an overwhelming desire to safeguard Yuta. Though she could sometimes heed Yuta's requests, her immense power often caused unintended harm. Known as the "Queen of Curses" for her limitless cursed energy and immense strength – a title acknowledged by Suguru Geto and Sukuna – her abilities included devastating physical attacks capable of tearing apart massive curses. She supported Yuta in combat, copying techniques like Cursed Speech using a conjured megaphone and transporting injured allies within a dark sack of cursed energy. During a confrontation with Geto, Yuta’s vow to join Rika in death unleashed her full potential, enabling her to fire a "Pure Love" energy blast that overpowered Geto’s Maximum: Uzumaki. After this battle, Gojo revealed Yuta had been the curse's source, dispelling it. Rika’s spirit appeared in her original human form, expressing gratitude to Yuta before peacefully departing. Following the exorcism, the remnants of Rika Orimoto's will persisted within a new cursed spirit bound to Yuta. This entity resembled the original but featured refined traits: a white skull-shaped head and more human-like arms. It lacked a strong individual ego, communicating minimally through short statements or uttering Yuta's name. Fully cooperative, it occasionally overreacted when protecting Yuta. The spirit could partially manifest for physical assistance or fully manifest for five minutes via a connection through Rika’s ring. In this fully manifested state, it granted Yuta immense shared cursed energy exceeding even Satoru Gojo's reserves, access to cursed techniques copied by consuming opponents' body parts, and an arsenal of cursed tools stored within its body. During conflicts like the Culling Game, it demonstrated high durability and strength capable of immobilizing Yuji Itadori, acting with tactical synergy alongside Yuta to defeat adversaries like Dhruv Lakdawalla or counter Ryu Ishigori’s attacks. The spirit prioritized Yuta’s orders above all else, remaining at designated posts unless summoned; however, its protective instincts could amplify its power during critical moments, such as breaking through domain barriers when unable to reach him.