Mina Fukuhara (born 1971) was a Japanese student who went to high school in Kabukicho, Tokyo during the 1980s. She dated her classmate Tat Miyoshi, but she was forced by Sachiko Kojima to sell her underwear for money; by December 1988; she was becoming too busy to date her boyfriend, and, when they went out on dates, Fukuhara bought large amounts of lingerie. On 14 December, Miyoshi argued with her after finding ¥200,000 ($2,203.50 in USD today) in her purse, suspecting that she was cheating on him or even prostituting herself. She ran off rather than reveal her side business, and Miyoshi persuaded Kazuma Kiryu to investigate on his behalf.
Kiryu found out that Fukuhara was, instead, selling her undergarments for money as a "burusera" girl. He attempted to convince her to give up this job, Fukuhara revealing to him that Kojima was forcing her to continue working for her; if she quit, she would be bullied relentlessly by the other girls at school. Kiryu would eventually find Kojima and eventually convinced her to stop running her business, freeing Fukuhara.