Mii Takahashi is a Japanese voice actress and singer from Tokyo, born on March 28, 1998. She began her career in entertainment after winning second place in the first All-Japan Beautiful Voice Contest in 2014, a competition organized by Oscar Promotion and Aoni Production that drew over fourteen thousand applicants. Her debut voice role came later that same year in the animated film Pretty Cure All Stars New Stage 3: Eternal Friends. In 2015, she became a member of the voice actress idol group elfin', where she performed until the group's activities concluded in September 2017. She stands 156 cm tall.

Takahashi is best known for her role as Eriko in the 2017 television anime series Elegant Yokai Apartment Life. Her other early anime appearances include roles in Concrete Revolutio, the educational series Pikaia! where she voiced the character Mii, and My Hero Academia as a female student. She also voiced characters in several video games, including Houkago Girls' Tribe as Miharu Uesugi, Aozora Under Girls! as Miyuki Shirabyōshi, and an early role in Kemono Friends.

Around April 2021, Takahashi changed her stage name to Shio Kisui. Under this new name, she has taken on more prominent roles. She is now widely recognized as the second voice actress for Yuika Mitsumine in The Idolmaster Shiny Colors franchise, a role she began performing in 2022. She also voices Daring Heart in Uma Musume Pretty Derby. Other anime credits under the name Shio Kisui include appearances in RPG Real Estate, Shine Post, The Masterful Cat Is Depressed Again Today, My Love Story with Yamada-kun at Lv999, The Dangers in My Heart, and Villainess Level 99. In addition to voice work, she has performed theme songs as part of elfin' and contributed vocals to character songs from The Idolmaster Shiny Colors franchise.