Yū Wakui is a Japanese voice actress and actress born on January 24, 1995, in Tochigi Prefecture, Japan. She is represented by the talent agency Mitt Management. Wakui stands 166 cm tall and has a background in classical ballet, which she studied from a young age, as well as experience in calligraphy, piano, and flute.

Wakui's career in voice acting began in 2014 with her debut role as Sumire Hikami in the Aikatsu! franchise. She voiced this character across multiple installments, including the television series Aikatsu!, Aikatsu Stars!, and Aikatsu on Parade!, as well as in several animated films such as Aikatsu! The Movie, Aikatsu! Music Award: Minna de Shō o Moraima SHOW!, and Aikatsu! ~Nerawareta Mahō no Aikatsu! Card~. Her early career also included a main role in 2016 as Yōko Nishikawa in the television series Three Leaves, Three Colors.

In 2020, she began voicing Tōru Asakura in The IDOLM@STER Shiny Colors series of singing video games, a role she has continued to reprise in subsequent game releases, live concerts, and tie-in music albums. Many of these albums have charted highly on the Oricon music charts, with several reaching the top ten. She also played the role of Maylene in the 2020 series By the Grace of the Gods.

More recently, in 2023, Wakui took on the lead role of Shiori Goshiki in the anime adaptation of A Galaxy Next Door. Her other notable anime credits include Hannah in Restaurant to Another World, Sūro in Kaina of the Great Snow Sea, and Lucia Lorca in Delico's Nursery.

Throughout her career, Wakui has had recurring collaborations with the Aikatsu! franchise, portraying Sumire Hikami across numerous series, films, and games for several years. She has also had a long-standing collaboration with The IDOLM@STER Shiny Colors franchise since 2020. She was previously affiliated with Himawari Theatre Group and Sunaoka Office before becoming a freelancer and then joining Mitt Management in January 2023.