Mayu Watanabe was a Japanese voice actor and entertainer, born on March 26, 1994, in Saitama Prefecture. Her career in the entertainment industry began in 2006 when she successfully joined the prominent idol group AKB48 as a third-generation trainee. This launched a prolific career as a singer and actor, with voice acting becoming a notable facet of her professional portfolio.

Watanabe's entry into voice acting occurred in 2012 when she was cast in the anime series AKB0048, a science fiction narrative that featured voice roles for several members of AKB48 and its sister groups. In this series, she voiced the main character Chieri Sono, a role she would reprise for its subsequent season. Her involvement with the project extended to music, as she became part of the official voice actor unit NO NAME, which performed the series' opening and closing theme songs.

In the same year, Watanabe took on a lead voice role in the anime film Psychic School Wars, also known as Nerawareta Gakuen. She portrayed Natsuki Suzuura, an athletic and vivacious middle school student who is a close friend of the protagonist. The film, produced by Sunrise and released in November 2012, featured a notable cast that included Kana Hanazawa and Daisuke Ono. Her connection to this project was further highlighted by her solo single Hikaru Monotachi, the B-side of which, Sayonara no Hashi, served as the film's theme song.

Her work in voice acting also included dubbing for foreign films. In 2013, she provided the Japanese-language voice for the女主角 in the film Percy Jackson: Sea of Monsters. She also made a cameo appearance as herself in the Maho Girls Precure! anime series.

Watanabe's career was closely tied to her tenure with AKB48, from which she graduated in 2017 to focus on acting and music. She continued to work in television and stage productions until 2020. On June 1, 2020, her agency announced her retirement from the entertainment industry due to health reasons, bringing her public career to a close.