In 2015, Saitō attended an audition for the role of You Watanabe from the anime television series Love Live! Sunshine!! part and got the role. She is part of the fictional group Aqours, which belongs to the Love Live! Franchise, and has released several singles with the group, which are very successful in Japan and some of which have received a gold record. At the eleventh Seiyū Awards in 2017, she received the Singing Award as a member of Aqours.
