Satori's homeroom teacher. Yoshikawa becomes involved in Muroe's kendo club out of concern for Satori's well-being. When Satori shows that she is capable of balancing kendo with school work, Yoshikawa continues to support the kendo club. She and Kojirou become friends and frequently chat when they are both in the staff room. She is skilled at playing video games. When Kojirou leaves the kendo club, Yoshikawa is requested by the club to become their advisor; she agrees to do so until she goes on maternity leave. The father of her baby is Kenzaburou, Kojirou's upperclassman.