Appearance and Personality
Fuyuki carries an intense desire for revenge against the Yukimura Zaibatsu, stemming from traumatic events in his childhood. He mostly remains cool and calculated to carry out his role in the Mikumo Boys' 20-year plan, however he is also seen to have a sense of humor when he toys with Akira.
Fuyuki spent his childhood in the rural industrial town of Mikumo 77. He was childhood friends with Sumio Kodai, Hanao Hiseki, and Riru Yukimura. The river near the town became gradually polluted by chemicals as a result of the activities of the Yukimura Zaibatsu. Due to the narcotic effects of the run-off, the protesting residents became gradually more violent. These riots became colloquially known as The Parade. During the Parade riots, Riru, abandoned by her parents as a "sacrifice", is targeted by townspeople who believe she is a witch. On August 2nd, 1979, she is taken from her home, raped, and killed by the crowd of rioters. For their efforts to rescue Riru, Fuyuki and his friends are attacked and disabled; Fuyuki's mouth was filled with oil and sewn shut, rendering him mute. After this, Fuyuki and his friends formed the Mikumo Boys, and began a 20-year plan to get revenge.
The Mikumo Boys met up repeatedly during this period to plan their operation. This is hinted at in the supplemental manga Pre-Lunatics, where Sumio mentions having a date with "two monkeys" during the events of case#0:lunatics. On July 11th, 1999, the plan went into action with the kidnapping of Chairman Yukimura and the destruction of the Yukimura Estate. Fuyuki took the chairman to another location, where he filmed two ransom videos demanding a 600 billion yen diamond, a purchase which ruins the Zaibatsu financially. On July 26th, Akira travelled to the Garbage Incineration Plant to exchange the diamond for Yukimura. Once he arrived, Fuyuki repeatedly toyed with Akira over the radio. During the exchange, Fuyuki committed suicide by jumping into a smokestack, destroying the diamond in the process. Later he and the other Mikumo Boys' plan was fulfilled by the complete destruction of the Yukimura Zaibatsu's board of directors, and finally the town of Mikumo 77 on the 20th anniversary of Riru's death.
- The Mikumo Boys represent the Japanese maxim of the "three wise monkeys", origin of the proverb "see no evil, speak no evil, hear no evil". The monkey who covers his mouth is known as Iwazaru, a name shared with a character from killer7.