Hachioji-P (八王子P), also known as 8#Prince, is a popular electropop producer and DJ. He mainly uses Miku, though he also uses Luka, GUMI, Rin, and Len. He also produced demo songs for anon & kanon and the private VOCALOID Akikoloid-chan.
Outside of the Vocaloid community, he produced Mayu Watanabe's song "Hikaru Monotachi" in 2012, which subsequently topped the Oricon Music charts. He's also a Happy and UK Hardcore producer under his P*Light alias, being a member of HARDCORE TANO*C and Konami's in-house label "beatnation records".