Minako Kotobuki ( born September 17, 1991) is a Japanese seiyu and singer born in Hyogo, Japan. She is best known for her role in K-On!. Her career as a musician began with her performance of the opening and ending themes of the anime series K-On! in April 2009. In the same month, she and three other voice actresses debuted as the musical group Sphere with their single "Future Stream".