TWICE Sana and Dahyun are posing at Mnet M Countdown' rearsal at CJ E & M Center in Sangam-dong, Seoul on the afternoon of the 15th.
About TWICE
Twice is a South Korean girl group formed by JYP Entertainment. The group is composed of nine members: Nayeon, Jeongyeon, Momo, Sana, Jihyo, Mina, Dahyun, Chaeyoung, and Tzuyu.
 Wikipedia