Yukako Yamagishi is a side character, former enemy and ally featured in Diamond is Unbreakable. She is featured centrally in the Yukako Yamagishi Falls in Love and the Yukako Yamagishi Dreams of Cinderella story arcs. Yukako is a high-school student besotted with Koichi Hirose. She originally tries to kidnap Koichi before being neutralized and eventually starting a mutual relationship with him. Struck with the Arrow by Keicho Nijimura, Yukako is a Stand User who freely manipulates her hair through Love Deluxe.