Hitomi Tadano bursts with energy and extroversion, sharply contrasting her older brother Hitohito’s reserved demeanor. Her short black twin tails and familiar facial features mirror his, though her petite, slender frame sets her apart. Sharing a bunk-bedded room with Hitohito, she enforces a playful "barrier" rule for privacy within their family home, which includes mother Jeanne and an unnamed father. Transitioning from third-year middle schooler to Itan High class representative, she excels athletically, boasting prefectural-level judo experience and soccer skills, while adeptly navigating digital tools. Her bold, proactive communication style includes creative ventriloquism—like voicing responses for Shousuke Komi, whom she mistakenly assumes struggles socially. Persistently engaging the aloof Shousuke, she playfully dubs him her "little brother," orchestrating his school schedules and event plans. Their dynamic flirts with romantic undertones as she balances mischief with genuine support. Simultaneously, she aids Hitohito’s budding romance with Shouko Komi, correcting her initial misunderstanding of his affections. She nudges him toward Komi with White Day gift advice, teases his hesitations, and even sniffs out Komi’s covert apartment visits. Family bonds shine through shared holidays—crafting Valentine’s gifts, collaborating on parental anniversary surprises—and her mischievous streak surfaces when she photographs Hitohito cross-dressing, jokingly hinting at transgender exploration to their mother. Consistent in her role as supportive sister and lively school participant, she peppers scenes with fourth-wall nudges and comedic misunderstandings, mistranslating romantic tensions for humor. Her narrative presence remains confined to core series events, uncharted by spin-offs or external media.