冨樫義博
is Kazuma's seventeen-year-old sister. She is an aspiring beautician and has a sixth sense even stronger than her brother's. It is Shizuru who recommends her brother see master Genkai for advice on the side effects of his sixth sense, getting him caught up in her tournament to find a pupil. Considerably down to earth and deadpan in most scenes, her role is mainly to act as the tough mother-figure to Kuwabara. Her role grows somewhat during the Dark Tournament, and appears again at the end of the series. However, in the anime she has a brief romantic connection to Sakyo as he saves her numerous times from demon guards at the stadium, and is given his lighter to remember him by as he dies in the stadium's destruction and takes over the role that Yusuke's mother had in the Sensui arc of the manga. Yoshihiro Togashi named Shizuru his favorite female character of the series "because she keeps her cool."