Yoko Obata is a Japanese former singer and voice actor born on October 17, 1968, in Tokyo's Taito Ward. She began her career in the entertainment industry in 1985, making her debut as both a singer and a voice actor at the same time. Her debut single, Fushigi-iro Happiness, served as the opening theme song for the television anime Mahō no Star Magical Emi. In a rare dual role for a newcomer, Obata also provided the voice for the series' protagonist, Mai Kazuki, and her magical alter ego, Magical Emi.

This role as Mai Kazuki and Magical Emi became the cornerstone of Obata's voice acting career. She reprised the character across several subsequent projects in the franchise during the mid-1980s. Her filmography as the character includes the original 1985 television series, the 1986 original video animation Adesugata Mahou no Sannin Musume, the 1986 OVA Mahō no Star Magical Emi: Semishigure, and the 1987 OVA Majokko Club Yoningumi - A Kuukan Kara no Alien X. Her work on the Magical Emi series closely intertwined her voice acting with her music career, as she also performed image songs for the character, such as the single Nangoku Ningyo Hime.

Beyond her work in animation, Obata was also active as an idol singer. In 1986, she contributed the character image song Moshimo Sora o Tobetara for the Studio Ghibli film Laputa: Castle in the Sky. During this period, she was known for a lively performance style, once earning the nickname Bishonure no Yoko, or Soaking Wet Yoko, for dousing herself with water at the end of a concert. In 1986, she formed the rock band YOCO & LOOK OUT with musicians including Sugai Yukio, later renaming the band LOOKOUT. After this band dissolved in 1989, she formed the band ESSEX in 1990 with Azuma Hiroshi, debuting with the single 100% Atsuku Nare in 1991. The band released the album POPPES in 1992 and disbanded the following year. After the dissolution of ESSEX in 1993, Obata retired from the entertainment industry and subsequently pursued a new career as a fashion designer or accessory designer. She made a brief television appearance on the Fuji TV program Jimoto Hasshin! Tokyo Jimoti in 2001 as a former classmate of singer Sanae Jounouchi.