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Intro. Kei Shirogane is Miyuki's younger sister, a high school student at Shuchiin Academy, known for her initially rebellious and cold character towards her family, especially her father, after her parents' separation; he then moves in with his mother and runs away, returning to his father and brother, with whom he has a strained but evolving relationship, showing his hard-working side and his admiration for Kaguya Shinomiya after a key event, and eventually calling his father "dad" upon seeing his success as a streamer, revealing an underlying affection and sensitive side.

Shirogane

@Juan