BOYSTYLE was a Japanese idol group formed in 2001, consisting of four members: Eri Murakawa, Asami Tano, Kayoko Uehara, and Yukina Kawata. The group debuted with the single "Boys be Stylish!" in July 2002, marking their entry into the competitive J-pop scene. BOYSTYLE released another single, "Empty World", in February 2003, followed by their debut album '02 Summer〜'03 Spring Collection 音 in March of the same year. The group gained significant attention with the release of "MIRAI" in December 2003 and "Kokoro no Chizu", which served as the opening theme for the popular anime series One Piece in November 2004, further boosting their popularity. In addition to these notable releases, BOYSTYLE also contributed the theme song "Hapiness" for the anime series Spiral: Suiri no Kizuna. In 2005, Yukina Kawata left the group, and BOYSTYLE continued as a trio until their official disbandment in 2007. During their active years, the group was known for their energetic performances and catchy pop tunes that resonated with fans. After the disbandment, some members pursued other ventures; Kayoko Uehara and Yukina Kawata formed Mansaku with ex-members of other J-pop groups, while Asami Tano and Eri Murakawa transitioned into acting careers. BOYSTYLE's contributions to the anime industry, particularly their theme song for One Piece, remain a notable part of their legacy in Japanese pop culture.