Rei Juggernaut holds the position of Third Column within Garderobe Academy’s Five Columns, an elite cadre of Otome operating under Headmistress Una Shamrock’s direct command. Her GEM, *Intensely Playing Peridot*, imbues her with combat prowess suited to her role, channeled through a massive two-handed sword wielded with relentless, power-focused strikes.

Rei becomes instrumental in Una Shamrock’s clandestine plot to eliminate Sifr Fran, whose access to ancient technology threatens global political hierarchies. She joins fellow Columns in clashes against Lena Sayers, a rogue former Otome whose sheer power renders Rei’s ferocious assaults ineffective—evidenced when Lena halts her sword strikes barehanded.

After Garderobe oversteps its authority by meddling in Windbloom Kingdom’s sovereignty, Rei and her comrades face disciplinary suspension orchestrated by Maria Graceburt, a senior Otome. This punitive measure exposes both the internal strife within Garderobe’s leadership and the far-reaching consequences of their politically charged actions.