Hitomi Mieno is a Japanese singer and songwriter who began her career in the mid-1990s, becoming known for her contributions to anime theme songs. Born on December 21, 1977 in Fukuoka Prefecture, she debuted as a singer in 1994 at the age of sixteen. Her entry into the music industry was directly tied to anime; she was discovered after participating in a karaoke contest for the Mashin Hero Wataru series, which led to her first recording opportunities.

Mieno's debut single, Hitomi ni Diamond, was released on June 22, 1994, and served as the ending theme for the anime series Lord of Lords Ryu Knight. This marked the beginning of a long pattern of her music being used in television animation. Later that same year, she performed RUN ~Kyo ga Kawaru Magic~, which became the second opening theme for the same series. Her early work also included theme songs for related media, such as radio dramas and the Legend of Crystania anime film, for which she sang the ending theme Hajimari no Bokensha-tachi in 1995.

Throughout the late 1990s, Mieno remained active in the anime music scene. She performed both the opening theme Hitotsu no Heart de and the ending theme BOYS BE AMBITIOUS for the 1997 series Cho Mashin Hero Wataru. The following year, she contributed another pair of songs to the same franchise with POWER OF DREAM and Ganbatte. In 2001, she sang Yukkuri, the ending theme for the anime Daa! Daa! Daa! (also known as UFO Baby), and Dearest, the opening theme for I My Me! Strawberry Eggs. Another notable anime credit from this period is the song W Infinity, performed with Hironobu Kageyama as Hitomi Mieno with Hironobu Kageyama, which was used as the opening theme for Gear Fighter Dendoh. Her later anime theme song work includes Kanadete Hoshi Uta, which was featured as an insert song in the 2010 series Mayoi Neko Overrun!.

As a recording artist, Mieno has released a substantial body of work. Her discography includes seventeen singles and eleven albums released since her debut. Her early albums include Ki Ra Ri Pi Ka Ri from 1995 and All Weather Girl from the same year. She continued releasing albums through the 1990s and 2000s, including Drum Can Salad (1997), Berry Roll (1998), 23.4 (1999), Saikyo Saikyo no Usotsuki ni Natte Yaru (2000), Baby Leaf (2001), and 2930 Nikumiso (2007). In 2014, she celebrated twenty years in the music industry with the release of the singles collection 20 Sai and the single Hitomi de Ele-phant!. Her work is primarily associated with the J-pop genre, and she has been signed to labels including Victor Entertainment.

Beyond her performance career, Mieno has also worked extensively as a lyricist for other artists. She has written lyrics for a wide range of singers and voice actors, including JAM Project,宫野真守 (Mamoru Miyano), 田中理恵 (Rie Tanaka), and 能登麻美子 (Mamiko Noto). Furthermore, she has built a significant parallel career as a screenwriter for anime series, working under the alias Deko Akao. In this capacity, she has served as a series composer or writer on numerous major titles, including Noragami, Arakawa Under the Bridge, Flying Witch, Komi Can't Communicate, and The Case Study of Vanitas. This dual role as both a theme song performer and a writer for the shows themselves makes her a unique creative figure in the anime industry, deeply embedded in the production of the medium beyond just its music.