Sayumi Michishige is a Japanese singer, actress and model. She is a former sixth-generation member and former leader of the J-pop group Morning Musume. Following the departure of fifth-generation member Risa Niigaki on October 12, 2013, Michishige held the longest tenure of any member in the group's history even after her graduation. She went on to hold this record until surpassed by ninth-generation members Mizuki Fukumura and Erina Ikuta in December 2022.

Morning Musume '24 , formerly and commonly known as Morning Musume and colloquially referred to as Momusu , is a Japanese girl group, holding the second highest overall single sales on the Oricon charts as of February 2012, with the Oricon record of most top-ten singles, having 64 of them.