Rinku Aimoto, a second-year Yoba Academy student and leader of DJ unit Happy Around!, grew up on Africa-adjacent Tio Tio Island with entomologist and zoologist parents. Her childhood immersion in African rhythms and wildlife fostered both a natural musical intuition and a habit of befriending animals, while stargazing alleviated loneliness after correspondence ceased with childhood friend Muni Ohnaruto. Japanese anime and manga became her cultural anchor during this isolated period.

Relocating to Japan alone during adolescence, she resided with her grandmother and encountered Maho Akashi at Yoba Academy, who sparked her DJ passion after witnessing Peaky P-key’s performance. This inspiration led Rinku to co-found Happy Around! with Maho, eventually reuniting with Muni and recruiting Rei Togetsu. Her leadership philosophy, emphasizing unity through symbolic seashell exchanges, mirrors her name’s dual meaning: "Aimoto" (愛本) blends "love" and "origin," while "Rinku" (リンク) phonetically signifies "link," resonating with her role as a connective force.

Exuberant and occasionally spacey, Rinku’s tropical upbringing surfaces in social eccentricities like addressing primates or misapplying idioms for comedic effect. Beneath her buoyant demeanor lies emotional complexity, particularly in reconciling fractured bonds with Muni, where vulnerabilities emerge through tearful confrontations. She tackles obstacles with guileless determination, oscillating between playful spontaneity and solemn introspection when peers underscore critical matters.

Her DJ sets channel innate rhythmic instincts, relying on full-body movement to navigate musical shifts. This organic approach catalyzes her evolution from tentative beginner to assured performer, mirroring the unit’s collective maturation. The group’s name derives from her signature spinning exclamation "Happy Around!"—a familial phrase. Notable traits include a pet chameleon (Leon), cold-weather aversion from tropical habitation, lion fascination, and a celestial namesake—the "Linking Star" christened by her astronaut sister, reinforcing cosmic and interpersonal connectivity themes.