Chuubou, Sonken

孫権仲謀

Introduced as Hakufu's younger sister during the Great Guardians season, a fact previously unknown to Hakufu. She appears highly knowledgeable, demonstrated by her ability to quote the legendary strategist Sun Tzu—an ironic detail given that the Sun family was said to descend from him—which stands in stark contrast to Hakufu, who struggles with reading. It is implied that she may harbor feelings for "Koukin Onii-sama."
It was later revealed that

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