Nayuta Yatonokami, younger twin in the rap duo cozmez, entered the world on December 24. Standing 163 cm tall with blood type B, his physical frailty traces back to chronic illness since birth, resulting in low stamina and rain sensitivity. This required constant care from his older brother Kanata, nurturing in Nayuta a dependence on his sibling and self-centered tendencies toward outsiders, alongside an absolute loyalty to Kanata. Their childhood endured severe maternal abuse until age 4, followed by institutionalization in a government facility that inflicted further mistreatment. The twins escaped at age 7, eventually settling in urban slums. Financial desperation drove Nayuta to secretly join Alter Trigger's phantometal experiments at 15. The experiments triggered progressive metal erosion in his arm, culminating in a suicide attempt at 17 when he leapt from a rooftop after telling his friend Shiki Ando, "The sky is beautiful." The event traumatized Shiki while Nayuta survived in a coma at an Alter Trigger facility. Unaware of Nayuta's survival, Kanata unconsciously generated a phantometal-powered illusion of his brother, performing alongside this projection in Paradox Live battles. Nayuta awoke from his coma upon hearing Kanata's music during a rap battle, sparking his recovery. Returning to the world, he reconciled with Shiki on that same rooftop, explaining his hospitalization and experimental treatment. He revealed to Kanata that Alter Trigger's facility preserved his life and reversed the metal erosion. This reunion propelled Nayuta to rejoin cozmez for the final battle against Buraikan, insisting Kanata's efforts must not be wasted. Typically, Nayuta exhibits apathy and energy-conserving behavior, frequently voicing wishes like, "I'm sleepy and I want to go home." Exceptions emerge in fierce protectiveness of Kanata and hip-hop passion. Despite emotional dependence, he displays greater rationality than his brother, evident when compelling Kanata to return Allen Sugasano's stolen phantometal. Creatively, he designs cozmez's costumes and co-writes lyrics echoing their traumatic history. A later confrontation with their abusive mother exposed unresolved trauma. Initially passive during her manipulative approach, Nayuta violently rejected her upon learning her scheme to abandon Kanata and steal their prize money. His ensuing emotional breakdown laid bare a lifelong yearning for maternal love, concluding with the brothers jointly expelling her from their home. Key relationships include his codependent bond with Kanata, whom he deems essential to existence ("Without Kanata, it's all meaningless"). His friendship with Shiki endured the initial betrayal trauma, demonstrated by their "Rooftop Friends" shuffle unit collaboration. Shared fashion interests connect him to Anne Faulkner and Reo Maruyama in Lollipop*universe, though he voiced frustration during a picnic when conversation strayed from music. His phantometal, the Ouroboros Pair Earring (right), activates by biting Kanata's matching left earring. The ouroboros motif symbolizes infinity, reflecting their inseparable bond. Personal aspirations center on "living freely," with favorite places being rooftops and Kanata's side. He enjoys gyoza and maintains a pragmatic worldview forged by lifelong hardship.