Mirei, the Libra Star Maiden of Granvania, descends from a family of palace mages dedicated to studying magic and Star Energy. A scientist at heart, she channels her intellect into engineering devices to control Star Energy and analyzing enigmatic beings called God’s Gifts. Her disciplined mind values logic above emotion, leading her to initially dismiss romance as a distraction from her work.

She sports short white hair accented by a purple-and-green headband and red glasses, her attire blending purple fabrics with green trimmings. Casual wear includes a sleek black swimsuit edged in turquoise and a yukata patterned with vibrant geometric shapes and cryptic script. Though pragmatic in relationships, she engages in rituals like Classmating purely to advance her research, unaware her detached curiosity toward Itsuki evolves into genuine affection. This unanticipated shift redirects her analytical focus from academic puzzles to understanding him as a person.

Depictions across media diverge: the game portrays her as methodical and aloof, resorting to drastic tactics like sedation and restraint during early encounters with Itsuki. As their dynamic deepens, she softens—flustered by public praise, acknowledging mistakes, and balancing her rigid ideals with empathy. The anime streamlines her growth, truncating her gradual bond with Itsuki, hastening her acceptance of romance, and minimizing her family’s legacy.

Beyond her studies, she relishes quiet baths, bitter coffee, and dense textbooks, while recoiling from chaos or disruptions. Her moral code fuels disdain for wrongdoing, and her stature makes her one of the tallest Star Maidens. Ever the innovator, she crafts experimental potions, sometimes skirting ethical lines in her pursuit of scientific breakthroughs.