Mihari Oyama

Mihari Oyama is the younger sister of Mahiro Oyama, a gifted individual who skipped grades to enroll at Yotsuha University and pursue a career in scientific research. Troubled by her brother's reclusive lifestyle, she secretly developed a drug that transformed Mahiro into a girl, setting her self-styled 'brother rehabilitation project' into motion. While she presents herself as a composed researcher meticulously tracking experimental data, she is in truth deeply devoted to her brother, consistently guiding and supporting him in his return to both social life and school through various means.