Yukako Yamagishi  

, 山岸 由花子

Yukako is a student who has fallen deeply in love with Koichi Hirose. Initially, her affection towards him was intense and aggressive, as she jealously attacked anyone she believed were rivals for his affections. She even went so far as to kidnap him and threaten his life if he did not reciprocate her feelings. However, this behavior backfired when Koichi became more attracted to Yukako due to the false rumors spread by Josuke and Okuyasu about his supposed insufferable nature. Despite realizing her mistake in trying to force Koichi's love, Yukako continued to pursue him, but this time she used a beauty-enhancing Cinderella stand called Aya Tsuji's Beauty Enhancing Stand. This stand transformed her into an attractive woman for a limited time and required the use of a special lipstick to maintain its power.