Rejena Simkhada, also known as Day and Hui Yat, is a Hong Kong-based artist born on June 4, 2002, of Nepalese-Hong Kong descent. She gained fame as the third-place finisher on the talent show 全民造星IV and is now a member of the Hong Kong girl group COLLAR and a contract artist with MakerVille. During high school, she joined the Kpop Cover dance group BRIGHTEN and reached the finals of the "2021 Hong Kong Region K-POP Dance Competition—CHOOM." She even trained as a K-pop trainee in South Korea over several holiday periods between 2018 and 2020 but had to cut it short due to the pandemic, financial reasons, and school commitments. In the 全民造星IV competition, she advanced by performing a dance and singing act, continuing to progress until securing third place by covering 鄭希怡's song "相對濕度" in the finals, where she was ranked fourth by the judges and second by the audience, earning a total of 36 points. On December 24, 2021, she debuted on with her group Lolly Talk, which later transitioned to COLLAR. They released their single "Call My Name!" on January 12, 2022. In March 2025, she released her first solo single "Wait A Second".