Tsuruko Aoyama (青山 鶴子 Aoyama Tsuruko) is Motoko Aoyama's elder sister and the one currently entrusted with the keeping of their family's dojo; the Shinmei-ryu school of swordsmanship. As she is not expected to be active in running the school, having given up the life of the sword for marriage, it is her duty to hand the school over to Motoko when she is ready.