Born Matsuki Mieko, she is better known by her stage name Matsuki Miyu, she was a Japanese voice actress from Kure, Hiroshima, best known for her work in anime. She was affiliated with 81 Produce at the time of her death.
After her announcement on July 14, 2015, Matsuki had been under treatment for acute pneumonia until her death on October 27, 2015 in Tokyo from lymphoma caused by Chronic active EBV infection. At the time of her death, she was cast as Charlotte Dimandias in the anime Hundred.
A charity event in her honour was held on September 11, 2016, at the Science Museum Hall in Chiyoda Ward, Tokyo, Japan. The 39! Miyu-chan event organized by her friends and colleagues had its proceeds go towards CAEBV research and related medical causes.