"Sing Out!" is the 23rd single by Japanese idol girl group Nogizaka46. The center position of the title track is held by Asuka Saito. It was released on 29 May 2019. It reached number-one on the weekly Oricon Singles Chart with 1,004,000 copies sold. It was also number-one on the Billboard Japan Hot 100.

Time Flies is the first greatest hits and second overall compilation album by Japanese idol girl group Nogizaka46. It was released on December 15, 2021, through N46Div., and Sony Music Records, two years and nine months after its predecessor studio album, Ima ga Omoide ni Naru made (2019) for the tenth-anniversary celebration of the group.